Bump to 0.12.0 (#1538)

* Add configurations for table headers

* lint

Co-authored-by: Amanita-Muscaria <nope>

.azure/azure-pipelines.yml

@@ -3,26 +3,26 @@ trigger:
 
 strategy:
   matrix:
-    linux-nightly:
-      image: ubuntu-16.04
+    linux-stable:
+      image: ubuntu-18.04
       style: 'unflagged'
-    macos-nightly:
+    macos-stable:
       image: macos-10.14
       style: 'unflagged'
-    windows-nightly:
-      image: vs2017-win2016
+    windows-stable:
+      image: windows-2019
       style: 'unflagged'
     linux-nightly-canary:
-      image: ubuntu-16.04
+      image: ubuntu-18.04
       style: 'canary'
     macos-nightly-canary:
       image: macos-10.14
       style: 'canary'
     windows-nightly-canary:
-      image: vs2017-win2016
+      image: windows-2019
       style: 'canary'
     fmt:
-      image: ubuntu-16.04
+      image: ubuntu-18.04
       style: 'fmt'
 
 pool:
@@ -35,18 +35,27 @@ steps:
       then
         sudo apt-get -y install libxcb-composite0-dev libx11-dev
       fi
-      curl https://sh.rustup.rs -sSf | sh -s -- -y --no-modify-path --default-toolchain `cat rust-toolchain`
-      export PATH=$HOME/.cargo/bin:$PATH
+      if [ "$(uname)" == "Darwin" ]; then
+        curl https://sh.rustup.rs -sSf | sh -s -- -y --no-modify-path --default-toolchain "stable"
+        export PATH=$HOME/.cargo/bin:$PATH
+      fi
+      rustup update
       rustc -Vv
       echo "##vso[task.prependpath]$HOME/.cargo/bin"
-      rustup component add rustfmt --toolchain `cat rust-toolchain`
+      rustup component add rustfmt
     displayName: Install Rust
-  - bash: RUSTFLAGS="-D warnings" cargo test --all-features
+  - bash: RUSTFLAGS="-D warnings" cargo test --all --features stable,test-bins
     condition: eq(variables['style'], 'unflagged')
     displayName: Run tests
-  - bash: NUSHELL_ENABLE_ALL_FLAGS=1 RUSTFLAGS="-D warnings" cargo test --all-features
+  - bash: RUSTFLAGS="-D warnings" cargo clippy --all --features=stable -- -D clippy::result_unwrap_used -D clippy::option_unwrap_used
+    condition: eq(variables['style'], 'unflagged')
+    displayName: Check clippy lints
+  - bash: NUSHELL_ENABLE_ALL_FLAGS=1 RUSTFLAGS="-D warnings" cargo test --all --features stable,test-bins
     condition: eq(variables['style'], 'canary')
     displayName: Run tests
+  - bash: NUSHELL_ENABLE_ALL_FLAGS=1 RUSTFLAGS="-D warnings" cargo clippy --all --features=stable -- -D clippy::result_unwrap_used -D clippy::option_unwrap_used
+    condition: eq(variables['style'], 'canary')
+    displayName: Check clippy lints
   - bash: cargo fmt --all -- --check
     condition: eq(variables['style'], 'fmt')
     displayName: Lint

.cargo/config

@@ -0,0 +1,3 @@
+[build]
+
+#rustflags = ["--cfg", "data_processing_primitives"]

.circleci/config.yml

@@ -38,7 +38,7 @@ workflows:
           extra_build_args: --cache-from=quay.io/nushell/nu-base:devel
           filters:
             branches:
-              ignore: 
+              ignore:
                 - master
           before_build:
             - pull_cache

.dockerignore

@@ -0,0 +1 @@
+target

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,30 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**Describe the bug**
+A clear and concise description of what the bug is.
+
+**To Reproduce**
+Steps to reproduce the behavior:
+1. 
+2. 
+3. 
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Screenshots**
+If applicable, add screenshots to help explain your problem.
+
+**Configuration (please complete the following information):**
+ - OS: [e.g. Windows]
+ - Version [e.g. 0.4.0]
+ - Optional features (if any)
+
+Add any other context about the problem here.

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,20 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+
+**Describe the solution you'd like**
+A clear and concise description of what you want to happen.
+
+**Describe alternatives you've considered**
+A clear and concise description of any alternative solutions or features you've considered.
+
+**Additional context**
+Add any other context or screenshots about the feature request here.

.github/workflows/docker-publish.yml

@@ -2,7 +2,7 @@ name: Publish consumable Docker images
 
 on:
   push:
-    tags: ['*.*.*']
+    tags: ['v?[0-9]+.[0-9]+.[0-9]+*']
 
 jobs:
   compile:
@@ -14,7 +14,11 @@ jobs:
         - x86_64-unknown-linux-gnu
     steps:
     - uses: actions/checkout@v1
-    - run: cargo install cross
+    - name: Install rust-embedded/cross
+      env: { VERSION: v0.1.16 }
+      run: >-
+        wget -nv https://github.com/rust-embedded/cross/releases/download/${VERSION}/cross-${VERSION}-x86_64-unknown-linux-gnu.tar.gz
+        -O- | sudo tar xz -C /usr/local/bin/
     - name: compile for specific target
       env: { arch: '${{ matrix.arch }}' }
       run: |
@@ -31,6 +35,10 @@ jobs:
     name: Build and publish docker images
     needs: compile
     runs-on: ubuntu-latest
+    env:
+      DOCKER_REGISTRY: quay.io/nushell
+      DOCKER_PASSWORD: ${{ secrets.DOCKER_REGISTRY }}
+      DOCKER_USER: ${{ secrets.DOCKER_USER }}
     strategy:
       matrix:
         tag:
@@ -44,55 +52,67 @@ jobs:
         - glibc
         - musl
         include:
-        - { tag: alpine,           base-image: alpine,                     arch: x86_64-unknown-linux-musl, plugin: true    }
-        - { tag: slim,             base-image: 'debian:stable-slim',       arch: x86_64-unknown-linux-gnu,  plugin: true    }
-        - { tag: debian,           base-image: debian,                     arch: x86_64-unknown-linux-gnu,  plugin: true    }
-        - { tag: glibc-busybox,    base-image: 'busybox:glibc',            arch: x86_64-unknown-linux-gnu,  use-patch: true }
-        - { tag: musl-busybox,     base-image: 'busybox:musl',             arch: x86_64-unknown-linux-musl,                 }
-        - { tag: musl-distroless,  base-image: 'gcr.io/distroless/static', arch: x86_64-unknown-linux-musl,                 }
-        - { tag: glibc-distroless, base-image: 'gcr.io/distroless/cc',     arch: x86_64-unknown-linux-gnu,  use-patch: true }
-        - { tag: glibc,            base-image: scratch,                    arch: x86_64-unknown-linux-gnu,                  }
-        - { tag: musl,             base-image: scratch,                    arch: x86_64-unknown-linux-musl,                 }
+        - { tag: alpine,           base-image: alpine,                     arch: x86_64-unknown-linux-musl, plugin: true,  use-patch: false}
+        - { tag: slim,             base-image: 'debian:stable-slim',       arch: x86_64-unknown-linux-gnu,  plugin: true,  use-patch: false}
+        - { tag: debian,           base-image: debian,                     arch: x86_64-unknown-linux-gnu,  plugin: true,  use-patch: false}
+        - { tag: glibc-busybox,    base-image: 'busybox:glibc',            arch: x86_64-unknown-linux-gnu,  plugin: false, use-patch: true }
+        - { tag: musl-busybox,     base-image: 'busybox:musl',             arch: x86_64-unknown-linux-musl, plugin: false, use-patch: false}
+        - { tag: musl-distroless,  base-image: 'gcr.io/distroless/static', arch: x86_64-unknown-linux-musl, plugin: false, use-patch: false}
+        - { tag: glibc-distroless, base-image: 'gcr.io/distroless/cc',     arch: x86_64-unknown-linux-gnu,  plugin: false, use-patch: true }
+        - { tag: glibc,            base-image: scratch,                    arch: x86_64-unknown-linux-gnu,  plugin: false, use-patch: false}
+        - { tag: musl,             base-image: scratch,                    arch: x86_64-unknown-linux-musl, plugin: false, use-patch: false}
     steps:
     - uses: actions/checkout@v1
     - uses: actions/download-artifact@master
       with: { name: '${{ matrix.arch }}', path: target/release }
     - name: Build and publish exact version
-      run: |
-        REGISTRY=${REGISTRY,,}; export TAG=${GITHUB_REF##*/}-${{ matrix.tag }};
+      run: |-
+        export DOCKER_TAG=${GITHUB_REF##*/}-${{ matrix.tag }}
         export NU_BINS=target/release/$( [ ${{ matrix.plugin }} = true ] && echo nu* || echo nu )
         export PATCH=$([ ${{ matrix.use-patch }} = true ] && echo .${{ matrix.tag }} || echo '')
         chmod +x $NU_BINS
 
-        echo ${{ secrets.DOCKER_REGISTRY }} | docker login docker.pkg.github.com -u ${{ github.actor }} --password-stdin
+        echo ${DOCKER_PASSWORD} | docker login ${DOCKER_REGISTRY} -u ${DOCKER_USER} --password-stdin
         docker-compose --file docker/docker-compose.package.yml build
         docker-compose --file docker/docker-compose.package.yml push              # exact version
       env:
         BASE_IMAGE: ${{ matrix.base-image }}
-        REGISTRY: docker.pkg.github.com/${{ github.repository }}
 
     #region semantics tagging
-    - name: Retag and push without suffixing version
-      run: |
+    - name: Retag and push with suffixed version
+      run: |-
         VERSION=${GITHUB_REF##*/}
-        docker tag ${REGISTRY,,}/nu:${VERSION}-${{ matrix.tag }} ${REGISTRY,,}/nu:${{ matrix.tag }}
-        docker tag ${REGISTRY,,}/nu:${VERSION}-${{ matrix.tag }} ${REGISTRY,,}/nu:${VERSION%%.*}-${{ matrix.tag }}
-        docker tag ${REGISTRY,,}/nu:${VERSION}-${{ matrix.tag }} ${REGISTRY,,}/nu:${VERSION%.*}-${{ matrix.tag }}
-        docker push ${REGISTRY,,}/nu:${VERSION%.*}-${{ matrix.tag }}              # latest patch
-        docker push ${REGISTRY,,}/nu:${VERSION%%.*}-${{ matrix.tag }}             # latest features
-        docker push ${REGISTRY,,}/nu:${{ matrix.tag }}                            # latest version
-      env: { REGISTRY: 'docker.pkg.github.com/${{ github.repository }}' }
+
+        latest_version=${VERSION%%%.*}-${{ matrix.tag }}
+        latest_feature=${VERSION%%.*}-${{ matrix.tag }}
+        latest_patch=${VERSION%.*}-${{ matrix.tag }}
+        exact_version=${VERSION}-${{ matrix.tag }}
+
+        tags=( ${latest_version} ${latest_feature} ${latest_patch} ${exact_version} )
+
+        for tag in ${tags[@]}; do
+          docker tag ${DOCKER_REGISTRY}/nu:${VERSION}-${{ matrix.tag }} ${DOCKER_REGISTRY}/nu:${tag}
+          docker push ${DOCKER_REGISTRY}/nu:${tag}
+        done
+
+        # latest version
+        docker tag ${DOCKER_REGISTRY}/nu:${VERSION}-${{ matrix.tag }} ${DOCKER_REGISTRY}/nu:${{ matrix.tag }}
+        docker push ${DOCKER_REGISTRY}/nu:${{ matrix.tag }}
+
     - name: Retag and push debian as latest
       if: matrix.tag == 'debian'
-      run: |
+      run: |-
         VERSION=${GITHUB_REF##*/}
-        docker tag ${REGISTRY,,}/nu:${{ matrix.tag }} ${REGISTRY,,}/nu:latest
-        docker tag ${REGISTRY,,}/nu:${VERSION}-${{ matrix.tag }} ${REGISTRY,,}/nu:${VERSION%.*}
-        docker tag ${REGISTRY,,}/nu:${VERSION}-${{ matrix.tag }} ${REGISTRY,,}/nu:${VERSION%%.*}
-        docker tag ${REGISTRY,,}/nu:${VERSION}-${{ matrix.tag }} ${REGISTRY,,}/nu:${VERSION}
-        docker push ${REGISTRY,,}/nu:${VERSION}       # exact version
-        docker push ${REGISTRY,,}/nu:${VERSION%%.*}   # latest features
-        docker push ${REGISTRY,,}/nu:${VERSION%.*}    # latest patch
-        docker push ${REGISTRY,,}/nu:latest           # latest version
-      env: { REGISTRY: 'docker.pkg.github.com/${{ github.repository }}' }
+
+        # ${latest features} ${latest patch} ${exact version}
+        tags=( ${VERSION%%.*} ${VERSION%.*} ${VERSION} )
+
+        for tag in ${tags[@]}; do
+          docker tag ${DOCKER_REGISTRY}/nu:${VERSION}-${{ matrix.tag }} ${DOCKER_REGISTRY}/nu:${tag}
+          docker push ${DOCKER_REGISTRY}/nu:${tag}
+        done
+
+        # latest version
+        docker tag ${DOCKER_REGISTRY}/nu:${{ matrix.tag }} ${DOCKER_REGISTRY}/nu:latest
+        docker push ${DOCKER_REGISTRY}/nu:latest
     #endregion semantics tagging

.gitignore

@@ -3,6 +3,7 @@
 **/*.rs.bk
 history.txt
 tests/fixtures/nuplayground
+crates/*/target
 
 # Debian/Ubuntu
 debian/.debhelper/

.gitpod.Dockerfile

@@ -1,7 +1,9 @@
 FROM gitpod/workspace-full
-USER root
-RUN apt-get update && apt-get install -y libssl-dev \
-    libxcb-composite0-dev \
-    pkg-config \
-    curl \
-    rustc
+
+USER gitpod
+
+RUN sudo apt-get update && \
+    sudo apt-get install -y \
+        libssl-dev \
+        libxcb-composite0-dev \
+        pkg-config

.gitpod.yml

@@ -1,8 +1,8 @@
 image:
   file: .gitpod.Dockerfile
 tasks:
-  - init: cargo build
-    command: cargo run
+  - init: cargo install --path . --force --features=stable
+    command: nu
 github:
   prebuilds:
     # enable for the master/default branch (defaults to true)
@@ -19,3 +19,11 @@ github:
     addBadge: false
     # add a label once the prebuild is ready to pull requests (defaults to false)
     addLabel: prebuilt-in-gitpod
+vscode:
+  extensions:
+    - hbenl.vscode-test-explorer@2.15.0:koqDUMWDPJzELp/hdS/lWw==
+    - Swellaby.vscode-rust-test-adapter@0.11.0:Xg+YeZZQiVpVUsIkH+uiiw==
+    - serayuzgur.crates@0.4.7:HMkoguLcXp9M3ud7ac3eIw==
+    - belfz.search-crates-io@1.2.1:kSLnyrOhXtYPjQpKnMr4eQ==
+    - vadimcn.vscode-lldb@1.4.5:lwHCNwtm0kmOBXeQUIPGMQ==
+    - bungcip.better-toml@0.3.2:3QfgGxxYtGHfJKQU7H0nEw==

Cargo.toml

@@ -1,179 +1,176 @@
 [package]
 name = "nu"
-version = "0.4.0"
-authors = ["Yehuda Katz <wycats@gmail.com>", "Jonathan Turner <jonathan.d.turner@gmail.com>", "Andrés N. Robalino <andres@androbtech.com>"]
-description = "A shell for the GitHub era"
+version = "0.12.0"
+authors = ["The Nu Project Contributors"]
+description = "A new kind of shell"
 license = "MIT"
 edition = "2018"
 readme = "README.md"
 default-run = "nu"
 repository = "https://github.com/nushell/nushell"
 homepage = "https://www.nushell.sh"
-documentation = "https://book.nushell.sh"
+documentation = "https://www.nushell.sh/book/"
+exclude = ["images"]
+
+[workspace]
+members = ["crates/*/"]
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-rustyline = "5.0.3"
-chrono = { version = "0.4.9", features = ["serde"] }
-derive-new = "0.5.8"
-prettytable-rs = "0.8.0"
-itertools = "0.8.0"
-ansi_term = "0.12.1"
-nom = "5.0.0"
-dunce = "1.0.0"
-indexmap = { version = "1.2.0", features = ["serde-1"] }
-chrono-humanize = "0.0.11"
-byte-unit = "3.0.1"
-base64 = "0.10.1"
-futures-preview = { version = "=0.3.0-alpha.18", features = ["compat", "io-compat"] }
-async-stream = "0.1.1"
-futures_codec = "0.2.5"
-num-traits = "0.2.8"
-term = "0.5.2"
-bytes = "0.4.12"
-log = "0.4.8"
-pretty_env_logger = "0.3.1"
-serde = { version = "1.0.100", features = ["derive"] }
-bson = { version = "0.14.0", features = ["decimal128"] }
-serde_json = "1.0.40"
-serde-hjson = "0.9.1"
-serde_yaml = "0.8"
-serde_bytes = "0.11.2"
-getset = "0.0.8"
-language-reporting = "0.4.0"
-app_dirs = "1.2.1"
-csv = "1.1"
-toml = "0.5.3"
+nu-cli = { version = "0.12.0", path = "./crates/nu-cli" }
+nu-source = { version = "0.12.0", path = "./crates/nu-source" }
+nu-plugin = { version = "0.12.0", path = "./crates/nu-plugin" }
+nu-protocol = { version = "0.12.0", path = "./crates/nu-protocol" }
+nu-errors = { version = "0.12.0", path = "./crates/nu-errors" }
+nu-parser = { version = "0.12.0", path = "./crates/nu-parser" }
+nu-value-ext = { version = "0.12.0", path = "./crates/nu-value-ext" }
+nu_plugin_average = { version = "0.12.0", path = "./crates/nu_plugin_average", optional=true }
+nu_plugin_binaryview = { version = "0.12.0", path = "./crates/nu_plugin_binaryview", optional=true }
+nu_plugin_fetch = { version = "0.12.0", path = "./crates/nu_plugin_fetch", optional=true }
+nu_plugin_inc = { version = "0.12.0", path = "./crates/nu_plugin_inc", optional=true }
+nu_plugin_match = { version = "0.12.0", path = "./crates/nu_plugin_match", optional=true }
+nu_plugin_post = { version = "0.12.0", path = "./crates/nu_plugin_post", optional=true }
+nu_plugin_ps = { version = "0.12.0", path = "./crates/nu_plugin_ps", optional=true }
+nu_plugin_str = { version = "0.12.0", path = "./crates/nu_plugin_str", optional=true }
+nu_plugin_sys = { version = "0.12.0", path = "./crates/nu_plugin_sys", optional=true }
+nu_plugin_textview = { version = "0.12.0", path = "./crates/nu_plugin_textview", optional=true }
+nu_plugin_tree = { version = "0.12.0", path = "./crates/nu_plugin_tree", optional=true }
+nu-macros = { version = "0.12.0", path = "./crates/nu-macros" }
+
+crossterm = { version = "0.16.0", optional = true }
+onig_sys = { version = "=69.1.0", optional = true }
+semver = { version = "0.9.0", optional = true }
+syntect = { version = "3.2.0", optional = true }
+url = { version = "2.1.1", optional = true }
+
 clap = "2.33.0"
-git2 = { version = "0.10.1", default_features = false }
-dirs = "2.0.2"
-glob = "0.3.0"
-ctrlc = "3.1.3"
-surf = "1.0.2"
-url = "2.1.0"
-roxmltree = "0.7.0"
-nom_locate = "1.0.0"
-nom-tracable = "0.4.0"
-unicode-xid = "0.2.0"
-serde_ini = "0.2.0"
-subprocess = "0.1.18"
-mime = "0.3.14"
-pretty-hex = "0.1.0"
-hex = "0.3.2"
-tempfile = "3.1.0"
-semver = "0.9.0"
-which = "2.0.1"
-textwrap = {version = "0.11.0", features = ["term_size"]}
-shellexpand = "1.0.0"
-futures-timer = "0.4.0"
-pin-utils = "0.1.0-alpha.4"
-num-bigint = { version = "0.2.3", features = ["serde"] }
-bigdecimal = { version = "0.1.0", features = ["serde"] }
-natural = "0.3.0"
-serde_urlencoded = "0.6.1"
-sublime_fuzzy = "0.5"
-
-regex = {version = "1", optional = true }
-neso = { version = "0.5.0", optional = true }
-crossterm = { version = "0.10.2", optional = true }
-syntect = {version = "3.2.0", optional = true }
-onig_sys = {version = "=69.1.0", optional = true }
-heim = {version = "0.0.8", optional = true }
-battery = {version = "0.7.4", optional = true }
-rawkey = {version = "0.1.2", optional = true }
-clipboard = {version = "0.5", optional = true }
-ptree = {version = "0.2", optional = true }
-image = { version = "0.22.2", default_features = false, features = ["png_codec", "jpeg"], optional = true }
-
-[features]
-default = ["textview", "sys", "ps"]
-raw-key = ["rawkey", "neso"]
-textview = ["syntect", "onig_sys", "crossterm"]
-binaryview = ["image", "crossterm"]
-sys = ["heim", "battery"]
-ps = ["heim"]
-# trace = ["nom-tracable/trace"]
-all = ["raw-key", "textview", "binaryview", "sys", "ps", "clipboard", "ptree"]
-
-[dependencies.rusqlite]
-version = "0.20.0"
-features = ["bundled", "blob"]
+ctrlc = "3.1.4"
+dunce = "1.0.0"
+futures = { version = "0.3", features = ["compat", "io-compat"] }
+log = "0.4.8"
+pretty_env_logger = "0.4.0"
 
 [dev-dependencies]
 pretty_assertions = "0.6.1"
+nu-test-support = { version = "0.12.0", path = "./crates/nu-test-support" }
 
 [build-dependencies]
-toml = "0.5.3"
-serde = { version = "1.0.101", features = ["derive"] }
+toml = "0.5.6"
+serde = { version = "1.0.105", features = ["derive"] }
+nu-build = { version = "0.12.0", path = "./crates/nu-build" }
 
-[lib]
-name = "nu"
-path = "src/lib.rs"
+[features]
+# Test executables
+test-bins = []
+
+default = ["sys", "ps", "textview", "inc", "str"]
+stable = ["default", "starship-prompt", "binaryview", "match", "tree", "average", "post", "fetch", "clipboard-cli"]
+
+# Default
+textview = ["crossterm", "syntect", "onig_sys", "url", "nu_plugin_textview"]
+sys = ["nu_plugin_sys"]
+ps = ["nu_plugin_ps"]
+inc = ["semver", "nu_plugin_inc"]
+str = ["nu_plugin_str"]
+
+# Stable
+average = ["nu_plugin_average"]
+binaryview = ["nu_plugin_binaryview"]
+fetch = ["nu_plugin_fetch"]
+match = ["nu_plugin_match"]
+post = ["nu_plugin_post"]
+trace = ["nu-parser/trace"]
+tree = ["nu_plugin_tree"]
+
+clipboard-cli = ["nu-cli/clipboard-cli"]
+starship-prompt = ["nu-cli/starship-prompt"]
 
 [[bin]]
-name = "nu_plugin_inc"
-path = "src/plugins/inc.rs"
+name = "fail"
+path = "crates/nu-test-support/src/bins/fail.rs"
+required-features = ["test-bins"]
 
 [[bin]]
-name = "nu_plugin_sum"
-path = "src/plugins/sum.rs"
+name = "chop"
+path = "crates/nu-test-support/src/bins/chop.rs"
+required-features = ["test-bins"]
 
 [[bin]]
-name = "nu_plugin_embed"
-path = "src/plugins/embed.rs"
+name = "cococo"
+path = "crates/nu-test-support/src/bins/cococo.rs"
+required-features = ["test-bins"]
 
 [[bin]]
-name = "nu_plugin_add"
-path = "src/plugins/add.rs"
+name = "nonu"
+path = "crates/nu-test-support/src/bins/nonu.rs"
+required-features = ["test-bins"]
 
 [[bin]]
-name = "nu_plugin_edit"
-path = "src/plugins/edit.rs"
+name = "iecho"
+path = "crates/nu-test-support/src/bins/iecho.rs"
+required-features = ["test-bins"]
 
+# Core plugins that ship with `cargo install nu` by default
+# Currently, Cargo limits us to installing only one binary
+# unless we use [[bin]], so we use this as a workaround
 [[bin]]
-name = "nu_plugin_str"
-path = "src/plugins/str.rs"
-
-[[bin]]
-name = "nu_plugin_skip"
-path = "src/plugins/skip.rs"
-
-[[bin]]
-name = "nu_plugin_match"
-path = "src/plugins/match.rs"
-required-features = ["regex"]
-
-[[bin]]
-name = "nu_plugin_sys"
-path = "src/plugins/sys.rs"
-required-features = ["sys"]
-
-[[bin]]
-name = "nu_plugin_ps"
-path = "src/plugins/ps.rs"
-required-features = ["ps"]
-
-[[bin]]
-name = "nu_plugin_tree"
-path = "src/plugins/tree.rs"
-required-features = ["tree"]
-
-[[bin]]
-name = "nu_plugin_binaryview"
-path = "src/plugins/binaryview.rs"
-required-features = ["binaryview"]
-
-[[bin]]
-name = "nu_plugin_textview"
-path = "src/plugins/textview.rs"
+name = "nu_plugin_core_textview"
+path = "src/plugins/nu_plugin_core_textview.rs"
 required-features = ["textview"]
 
 [[bin]]
-name = "nu_plugin_docker"
-path = "src/plugins/docker.rs"
-required-features = ["docker"]
+name = "nu_plugin_core_inc"
+path = "src/plugins/nu_plugin_core_inc.rs"
+required-features = ["inc"]
 
+[[bin]]
+name = "nu_plugin_core_ps"
+path = "src/plugins/nu_plugin_core_ps.rs"
+required-features = ["ps"]
+
+[[bin]]
+name = "nu_plugin_core_str"
+path = "src/plugins/nu_plugin_core_str.rs"
+required-features = ["str"]
+
+[[bin]]
+name = "nu_plugin_core_sys"
+path = "src/plugins/nu_plugin_core_sys.rs"
+required-features = ["sys"]
+
+# Stable plugins
+[[bin]]
+name = "nu_plugin_stable_average"
+path = "src/plugins/nu_plugin_stable_average.rs"
+required-features = ["average"]
+
+[[bin]]
+name = "nu_plugin_stable_fetch"
+path = "src/plugins/nu_plugin_stable_fetch.rs"
+required-features = ["fetch"]
+
+[[bin]]
+name = "nu_plugin_stable_binaryview"
+path = "src/plugins/nu_plugin_stable_binaryview.rs"
+required-features = ["binaryview"]
+
+[[bin]]
+name = "nu_plugin_stable_match"
+path = "src/plugins/nu_plugin_stable_match.rs"
+required-features = ["match"]
+
+[[bin]]
+name = "nu_plugin_stable_post"
+path = "src/plugins/nu_plugin_stable_post.rs"
+required-features = ["post"]
+
+[[bin]]
+name = "nu_plugin_stable_tree"
+path = "src/plugins/nu_plugin_stable_tree.rs"
+required-features = ["tree"]
+
+# Main nu binary
 [[bin]]
 name = "nu"
 path = "src/main.rs"

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2019 Yehuda Katz, Jonathan Turner
+Copyright (c) 2019 - 2020 Yehuda Katz, Jonathan Turner
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

Makefile.toml

@@ -4,21 +4,12 @@ command = "lalrpop"
 args = ["src/parser/parser.lalrpop"]
 
 [tasks.baseline]
-dependencies = ["lalrpop"]
-
-[tasks.build]
 command = "cargo"
-args = ["build"]
-dependencies = ["lalrpop"]
+args = ["build", "--bins"]
 
 [tasks.run]
 command = "cargo"
-args = ["run", "--release"]
-dependencies = ["baseline"]
-
-[tasks.release]
-command = "cargo"
-args = ["build", "--release"]
+args = ["run"]
 dependencies = ["baseline"]
 
 [tasks.test]

README.md

@@ -1,3 +1,4 @@
+[![Gitpod Ready-to-Code](https://img.shields.io/badge/Gitpod-Ready--to--Code-blue?logo=gitpod)](https://gitpod.io/#https://github.com/nushell/nushell)
 [![Crates.io](https://img.shields.io/crates/v/nu.svg)](https://crates.io/crates/nu)
 [![Build Status](https://dev.azure.com/nushell/nushell/_apis/build/status/nushell.nushell?branchName=master)](https://dev.azure.com/nushell/nushell/_build/latest?definitionId=2&branchName=master)
 [![Discord](https://img.shields.io/discord/601130461678272522.svg?logo=discord)](https://discord.gg/NtAbbGn)
@@ -6,24 +7,33 @@
 
 # Nu Shell
 
-A modern shell for the GitHub era.
+A new type of shell.
 
 ![Example of nushell](images/nushell-autocomplete.gif "Example of nushell")
 
 # Status
 
-This project has reached a minimum-viable product level of quality. While contributors dogfood it as their daily driver, it may be unstable for some commands. Future releases will work to fill out missing features and improve stability. Its design is also subject to change as it matures.
+This project has reached a minimum-viable product level of quality.
+While contributors dogfood it as their daily driver, it may be unstable for some commands.
+Future releases will work to fill out missing features and improve stability.
+Its design is also subject to change as it matures.
 
-Nu comes with a set of built-in commands (listed below). If a command is unknown, the command will shell-out and execute it (using cmd on Windows or bash on Linux and macOS), correctly passing through stdin, stdout, and stderr, so things like your daily git workflows and even `vim` will work just fine.
+Nu comes with a set of built-in commands (listed below).
+If a command is unknown, the command will shell-out and execute it (using cmd on Windows or bash on Linux and macOS), correctly passing through stdin, stdout, and stderr, so things like your daily git workflows and even `vim` will work just fine.
 
 # Learning more
 
-There are a few good resources to learn about Nu. There is a [book](https://book.nushell.sh) about Nu that is currently in progress. The book focuses on using Nu and its core concepts.
+There are a few good resources to learn about Nu.
+There is a [book](https://www.nushell.sh/book/) about Nu that is currently in progress.
+The book focuses on using Nu and its core concepts.
 
-If you're a developer who would like to contribute to Nu, we're also working on a [book for developers](https://github.com/nushell/contributor-book/tree/master/en) to help you get started. There are also [good first issues](https://github.com/nushell/nushell/issues?q=is%3Aopen+is%3Aissue+label%3A%22good+first+issue%22) to help you dive in.
+If you're a developer who would like to contribute to Nu, we're also working on a [book for developers](https://www.nushell.sh/contributor-book/) to help you get started.
+There are also [good first issues](https://github.com/nushell/nushell/issues?q=is%3Aopen+is%3Aissue+label%3A%22good+first+issue%22) to help you dive in.
 
 We also have an active [Discord](https://discord.gg/NtAbbGn) and [Twitter](https://twitter.com/nu_shell) if you'd like to come and chat with us.
 
+You can also find more learning resources in our [documentation](https://www.nushell.sh/documentation.html) site.
+
 Try it in Gitpod.
 
 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/#https://github.com/nushell/nushell)
@@ -32,9 +42,9 @@ Try it in Gitpod.
 
 ## Local
 
-Up-to-date installation instructions can be found in the [installation chapter of the book](https://book.nushell.sh/en/installation).
+Up-to-date installation instructions can be found in the [installation chapter of the book](https://www.nushell.sh/book/en/installation.html).  **Windows users**: please note that Nu works on Windows 10 and does not currently have Windows 7/8.1 support.
 
-To build Nu, you will need to use the **nightly** version of the compiler.
+To build Nu, you will need to use the **latest stable (1.39 or later)** version of the compiler.
 
 Required dependencies:
 
@@ -46,20 +56,30 @@ Optional dependencies:
 * To use Nu with all possible optional features enabled, you'll also need the following:
   * on Linux (on Debian/Ubuntu): `apt install libxcb-composite0-dev libx11-dev`
 
-To install Nu via cargo (make sure you have installed [rustup](https://rustup.rs/) and the beta compiler via `rustup install beta`):
+To install Nu via cargo (make sure you have installed [rustup](https://rustup.rs/) and the latest stable compiler via `rustup install stable`):
 
 ```
-cargo +beta install nu
+cargo install nu
 ```
 
-You can also install Nu with all the bells and whistles (be sure to have installed the [dependencies](https://book.nushell.sh/en/installation#dependencies) for your platform):
+You can also build Nu yourself with all the bells and whistles (be sure to have installed the [dependencies](https://www.nushell.sh/book/en/installation.html#dependencies) for your platform), once you have checked out this repo with git:
 
 ```
-cargo +beta install nu --all-features
+cargo build --workspace --features=stable
 ```
 
 ## Docker
 
+### Quickstart
+
+Want to try Nu right away? Execute the following to get started.
+
+```bash
+docker run -it quay.io/nushell/nu:latest
+```
+
+### Guide
+
 If you want to pull a pre-built container, you can browse tags for the [nushell organization](https://quay.io/organization/nushell)
 on Quay.io. Pulling a container would come down to:
 
@@ -104,11 +124,18 @@ The second container is a bit smaller if the size is important to you.
 
 # Philosophy
 
-Nu draws inspiration from projects like PowerShell, functional programming languages, and modern CLI tools. Rather than thinking of files and services as raw streams of text, Nu looks at each input as something with structure. For example, when you list the contents of a directory, what you get back is a table of rows, where each row represents an item in that directory. These values can be piped through a series of steps, in a series of commands called a 'pipeline'.
+Nu draws inspiration from projects like PowerShell, functional programming languages, and modern CLI tools.
+Rather than thinking of files and services as raw streams of text, Nu looks at each input as something with structure.
+For example, when you list the contents of a directory, what you get back is a table of rows, where each row represents an item in that directory.
+These values can be piped through a series of steps, in a series of commands called a 'pipeline'.
 
 ## Pipelines
 
-In Unix, it's common to pipe between commands to split up a sophisticated command over multiple steps. Nu takes this a step further and builds heavily on the idea of _pipelines_. Just as the Unix philosophy, Nu allows commands to output from stdout and read from stdin. Additionally, commands can output structured data (you can think of this as a third kind of stream). Commands that work in the pipeline fit into one of three categories:
+In Unix, it's common to pipe between commands to split up a sophisticated command over multiple steps.
+Nu takes this a step further and builds heavily on the idea of _pipelines_.
+Just as the Unix philosophy, Nu allows commands to output from stdout and read from stdin.
+Additionally, commands can output structured data (you can think of this as a third kind of stream).
+Commands that work in the pipeline fit into one of three categories:
 
 * Commands that produce a stream (eg, `ls`)
 * Commands that filter a stream (eg, `where type == "Directory"`)
@@ -118,7 +145,7 @@ Commands are separated by the pipe symbol (`|`) to denote a pipeline flowing lef
 
 ```
 /home/jonathan/Source/nushell(master)> ls | where type == "Directory" | autoview
-━━━━┯━━━━━━━━━━━┯━━━━━━━━━━━┯━━━━━━━━━━┯━━━━━━━━┯━━━━━━━━━━━━━━┯━━━━━━━━━━━━━━━━
+────┬───────────┬───────────┬──────────┬────────┬──────────────┬────────────────
  #  │ name      │ type      │ readonly │ size   │ accessed     │ modified
 ────┼───────────┼───────────┼──────────┼────────┼──────────────┼────────────────
   0 │ .azure    │ Directory │          │ 4.1 KB │ 2 months ago │ a day ago
@@ -129,78 +156,107 @@ Commands are separated by the pipe symbol (`|`) to denote a pipeline flowing lef
   5 │ src       │ Directory │          │ 4.1 KB │ 2 months ago │ 37 minutes ago
   6 │ assets    │ Directory │          │ 4.1 KB │ a month ago  │ a month ago
   7 │ docs      │ Directory │          │ 4.1 KB │ 2 months ago │ 2 months ago
-━━━━┷━━━━━━━━━━━┷━━━━━━━━━━━┷━━━━━━━━━━┷━━━━━━━━┷━━━━━━━━━━━━━━┷━━━━━━━━━━━━━━━━
+────┴───────────┴───────────┴──────────┴────────┴──────────────┴────────────────
 ```
 
-Because most of the time you'll want to see the output of a pipeline, `autoview` is assumed. We could have also written the above:
+Because most of the time you'll want to see the output of a pipeline, `autoview` is assumed.
+We could have also written the above:
 
 ```
 /home/jonathan/Source/nushell(master)> ls | where type == Directory
 ```
 
-Being able to use the same commands and compose them differently is an important philosophy in Nu. For example, we could use the built-in `ps` command as well to get a list of the running processes, using the same `where` as above.
+Being able to use the same commands and compose them differently is an important philosophy in Nu.
+For example, we could use the built-in `ps` command as well to get a list of the running processes, using the same `where` as above.
 
 ```text
 /home/jonathan/Source/nushell(master)> ps | where cpu > 0
-━━━┯━━━━━━━┯━━━━━━━━━━━━━━━━━┯━━━━━━━━━━┯━━━━━━━━━━
+───┬───────┬─────────────────┬──────────┬──────────
  # │ pid   │ name            │ status   │ cpu
 ───┼───────┼─────────────────┼──────────┼──────────
  0 │   992 │ chrome          │ Sleeping │ 6.988768
  1 │  4240 │ chrome          │ Sleeping │ 5.645982
  2 │ 13973 │ qemu-system-x86 │ Sleeping │ 4.996551
  3 │ 15746 │ nu              │ Sleeping │ 84.59905
-━━━┷━━━━━━━┷━━━━━━━━━━━━━━━━━┷━━━━━━━━━━┷━━━━━━━━━━
-
+───┴───────┴─────────────────┴──────────┴──────────
 ```
 
 ## Opening files
 
-Nu can load file and URL contents as raw text or as structured data (if it recognizes the format). For example, you can load a .toml file as structured data and explore it:
+Nu can load file and URL contents as raw text or as structured data (if it recognizes the format).
+For example, you can load a .toml file as structured data and explore it:
 
 ```
 /home/jonathan/Source/nushell(master)> open Cargo.toml
-━━━━━━━━━━━━━━━━━━┯━━━━━━━━━━━━━━━━┯━━━━━━━━━━━━━━━━━━
+──────────────────┬────────────────┬──────────────────
  bin              │ dependencies   │ dev-dependencies
 ──────────────────┼────────────────┼──────────────────
  [table: 12 rows] │ [table: 1 row] │ [table: 1 row]
-━━━━━━━━━━━━━━━━━━┷━━━━━━━━━━━━━━━━┷━━━━━━━━━━━━━━━━━━
+──────────────────┴────────────────┴──────────────────
 ```
 
 We can pipeline this into a command that gets the contents of one of the columns:
 
 ```
 /home/jonathan/Source/nushell(master)> open Cargo.toml | get package
-━━━━━━━━━━━━━━━━━┯━━━━━━━━━━━━━━━━━━━━━━━━━━━━┯━━━━━━━━━┯━━━━━━━━━┯━━━━━━┯━━━━━━━━━
+─────────────────┬────────────────────────────┬─────────┬─────────┬──────┬─────────
  authors         │ description                │ edition │ license │ name │ version
 ─────────────────┼────────────────────────────┼─────────┼─────────┼──────┼─────────
- [table: 3 rows] │ A shell for the GitHub era │ 2018    │ MIT     │ nu   │ 0.4.0
-━━━━━━━━━━━━━━━━━┷━━━━━━━━━━━━━━━━━━━━━━━━━━━━┷━━━━━━━━━┷━━━━━━━━━┷━━━━━━┷━━━━━━━━━
+ [table: 3 rows] │ A shell for the GitHub era │ 2018    │ MIT     │ nu   │ 0.9.0
+─────────────────┴────────────────────────────┴─────────┴─────────┴──────┴─────────
 ```
 
 Finally, we can use commands outside of Nu once we have the data we want:
 
 ```
 /home/jonathan/Source/nushell(master)> open Cargo.toml | get package.version | echo $it
-0.4.0
+0.9.0
 ```
 
 Here we use the variable `$it` to refer to the value being piped to the external command.
 
+## Configuration
+
+Nu has early support for configuring the shell. It currently supports the following settings:
+
+| Variable        | Type                 | Description                                                    |
+| --------------- | -------------------- | -------------------------------------------------------------- |
+| path            | table of strings     | PATH to use to find binaries                                   |
+| env             | row                  | the environment variables to pass to external commands         |
+| ctrlc_exit      | boolean              | whether or not to exit Nu after multiple ctrl-c presses        |
+| table_mode      | "light" or other     | enable lightweight or normal tables                            |
+| edit_mode       | "vi" or "emacs"      | changes line editing to "vi" or "emacs" mode                   |
+| completion_mode | "circular" or "list" | changes completion type to "circular" (default) or "list" mode |
+
+To set one of these variables, you can use `config --set`. For example:
+
+```
+> config --set [edit_mode "vi"]
+> config --set [path $nu.path]
+```
+
 ## Shells
 
-Nu will work inside of a single directory and allow you to navigate around your filesystem by default. Nu also offers a way of adding additional working directories that you can jump between, allowing you to work in multiple directories at the same time.
+Nu will work inside of a single directory and allow you to navigate around your filesystem by default.
+Nu also offers a way of adding additional working directories that you can jump between, allowing you to work in multiple directories at the same time.
 
-To do so, use the `enter` command, which will allow you create a new "shell" and enter it at the specified path. You can toggle between this new shell and the original shell with the `p` (for previous) and `n` (for next), allowing you to navigate around a ring buffer of shells. Once you're done with a shell, you can `exit` it and remove it from the ring buffer.
+To do so, use the `enter` command, which will allow you create a new "shell" and enter it at the specified path.
+You can toggle between this new shell and the original shell with the `p` (for previous) and `n` (for next), allowing you to navigate around a ring buffer of shells.
+Once you're done with a shell, you can `exit` it and remove it from the ring buffer.
 
 Finally, to get a list of all the current shells, you can use the `shells` command.
 
 ## Plugins
 
-Nu supports plugins that offer additional functionality to the shell and follow the same structured data model that built-in commands use. This allows you to extend nu for your needs.
+Nu supports plugins that offer additional functionality to the shell and follow the same structured data model that built-in commands use.
+This allows you to extend nu for your needs.
 
 There are a few examples in the `plugins` directory.
 
-Plugins are binaries that are available in your path and follow a `nu_plugin_*` naming convention. These binaries interact with nu via a simple JSON-RPC protocol where the command identifies itself and passes along its configuration, which then makes it available for use. If the plugin is a filter, data streams to it one element at a time, and it can stream data back in return via stdin/stdout. If the plugin is a sink, it is given the full vector of final data and is given free reign over stdin/stdout to use as it pleases.
+Plugins are binaries that are available in your path and follow a `nu_plugin_*` naming convention.
+These binaries interact with nu via a simple JSON-RPC protocol where the command identifies itself and passes along its configuration, which then makes it available for use.
+If the plugin is a filter, data streams to it one element at a time, and it can stream data back in return via stdin/stdout.
+If the plugin is a sink, it is given the full vector of final data and is given free reign over stdin/stdout to use as it pleases.
 
 # Goals
 
@@ -217,98 +273,10 @@ Nu adheres closely to a set of goals that make up its design philosophy. As feat
 * Finally, Nu views data functionally. Rather than using mutation, pipelines act as a means to load, change, and save data without mutable state.
 
 # Commands
-## Initial commands
-| command | description |
-| ------------- | ------------- |
-| cd path | Change to a new path |
-| cp source path | Copy files |
-| date (--utc) | Get the current datetime |
-| fetch url | Fetch contents from a url and retrieve data as a table if possible |
-| help | Display help information about commands |
-| ls (path) | View the contents of the current or given path |
-| mkdir path | Make directories, creates intermediary directories as required. |
-| mv source target | Move files or directories. |
-| open filename | Load a file into a cell, convert to table if possible (avoid by appending '--raw') |
-| post url body (--user <user>) (--password <password>) | Post content to a url and retrieve data as a table if possible |
-| ps | View current processes |
-| sys | View information about the current system |
-| which filename | Finds a program file. |
-| rm   {file or directory} | Remove a file, (for removing directory append '--recursive') |
-| version | Display Nu version |
 
-## Shell commands
-| command | description |
-| ------- | ----------- |
-| exit (--now) | Exit the current shell (or all shells) |
-| enter (path) | Create a new shell and begin at this path |
-| p | Go to previous shell |
-| n | Go to next shell |
-| shells | Display the list of current shells |
-
-## Filters on tables (structured data)
-| command | description |
-| ------------- | ------------- |
-| add column-or-column-path value | Add a new column to the table |
-| edit column-or-column-path value | Edit an existing column to have a new value |
-| embed column | Creates a new table of one column with the given name, and places the current table inside of it |
-| first amount | Show only the first number of rows |
-| get column-or-column-path | Open column and get data from the corresponding cells |
-| inc (column-or-column-path) | Increment a value or version. Optionally use the column of a table |
-| last amount | Show only the last number of rows |
-| nth row-number | Return only the selected row |
-| pick ...columns | Down-select table to only these columns |
-| pivot --header-row <headers> | Pivot the tables, making columns into rows and vice versa |
-| reject ...columns | Remove the given columns from the table |
-| reverse | Reverses the table. |
-| skip amount | Skip a number of rows |
-| skip-while condition | Skips rows while the condition matches. |
-| sort-by ...columns | Sort by the given columns |
-| str (column) | Apply string function. Optionally use the column of a table |
-| sum | Sum a column of values |
-| tags | Read the tags (metadata) for values |
-| to-bson | Convert table into .bson binary data |
-| to-csv | Convert table into .csv text |
-| to-json | Convert table into .json text |
-| to-sqlite | Convert table to sqlite .db binary data |
-| to-toml | Convert table into .toml text |
-| to-tsv | Convert table into .tsv text |
-| to-url | Convert table to a urlencoded string |
-| to-yaml | Convert table into .yaml text |
-| where condition | Filter table to match the condition |
-
-## Filters on text (unstructured data)
-| command | description |
-| ------------- | ------------- |
-| from-bson | Parse binary data as .bson and create table |
-| from-csv | Parse text as .csv and create table |
-| from-ini | Parse text as .ini and create table |
-| from-json | Parse text as .json and create table |
-| from-sqlite | Parse binary data as sqlite .db and create table |
-| from-ssv --minimum-spaces <minimum number of spaces to count as a separator> | Parse text as space-separated values and create table |
-| from-toml | Parse text as .toml and create table |
-| from-tsv  | Parse text as .tsv and create table  |
-| from-url | Parse urlencoded string and create a table |
-| from-xml | Parse text as .xml and create a table |
-| from-yaml | Parse text as a .yaml/.yml and create a table |
-| lines | Split single string into rows, one per line |
-| size | Gather word count statistics on the text |
-| split-column sep ...column-names | Split row contents across multiple columns via the separator, optionally give the columns names |
-| split-row sep | Split row contents over multiple rows via the separator |
-| trim | Trim leading and following whitespace from text data |
-| {external-command} $it | Run external command with given arguments, replacing $it with each row text |
-
-## Consuming commands
-| command | description |
-| ------------- | ------------- |
-| autoview | View the contents of the pipeline as a table or list |
-| binaryview | Autoview of binary data (optional feature) |
-| clip | Copy the contents of the pipeline to the copy/paste buffer (optional feature) |
-| save filename | Save the contents of the pipeline to a file |
-| table | View the contents of the pipeline as a table |
-| textview | Autoview of text data |
-| tree | View the contents of the pipeline as a tree (optional feature) |
+You can find a list of Nu commands, complete with documentation, in [quick command references](https://www.nushell.sh/documentation.html#quick-command-references).
 
 # License
 
-The project is made available under the MIT license. See "LICENSE" for more information.
+The project is made available under the MIT license. See the `LICENSE` file for more information.
 

TODO.md

@@ -0,0 +1,60 @@
+This pattern is extremely repetitive and can be abstracted:
+
+```rs
+    let args = args.evaluate_once(registry)?;
+    let tag = args.name_tag();
+    let input = args.input;
+
+    let stream = async_stream! {
+        let values: Vec<Value> = input.values.collect().await;
+
+        let mut concat_string = String::new();
+        let mut latest_tag: Option<Tag> = None;
+
+        for value in values {
+            latest_tag = Some(value_tag.clone());
+            let value_span = value.tag.span;
+
+            match &value.value {
+                UntaggedValue::Primitive(Primitive::String(s)) => {
+                    concat_string.push_str(&s);
+                    concat_string.push_str("\n");
+                }
+                _ => yield Err(ShellError::labeled_error_with_secondary(
+                    "Expected a string from pipeline",
+                    "requires string input",
+                    name_span,
+                    "value originates from here",
+                    value_span,
+                )),
+
+            }
+        }
+
+```
+
+Mandatory and Optional in parse_command
+
+trace_remaining?
+
+select_fields and select_fields take unnecessary Tag
+
+Value#value should be Value#untagged
+
+Unify dictionary building, probably around a macro
+
+sys plugin in own crate
+
+textview in own crate
+
+Combine atomic and atomic_parse in parser
+
+at_end_possible_ws needs to be comment and separator sensitive
+
+Eliminate unnecessary `nodes` parser
+
+#[derive(HasSpan)]
+
+Figure out a solution for the duplication in stuff like NumberShape vs. NumberExpressionShape
+
+use `struct Expander` from signature.rs

build.rs

@@ -1,39 +1,3 @@
-use serde::Deserialize;
-use std::collections::HashMap;
-use std::collections::HashSet;
-use std::env;
-use std::path::Path;
-
-#[derive(Deserialize)]
-struct Feature {
-    #[allow(unused)]
-    description: String,
-    enabled: bool,
-}
-
 fn main() -> Result<(), Box<dyn std::error::Error>> {
-    let input = env::var("CARGO_MANIFEST_DIR").unwrap();
-    let all_on = env::var("NUSHELL_ENABLE_ALL_FLAGS").is_ok();
-    let flags: HashSet<String> = env::var("NUSHELL_ENABLE_FLAGS")
-        .map(|s| s.split(",").map(|s| s.to_string()).collect())
-        .unwrap_or_else(|_| HashSet::new());
-
-    if all_on && !flags.is_empty() {
-        println!(
-            "cargo:warning={}",
-            "Both NUSHELL_ENABLE_ALL_FLAGS and NUSHELL_ENABLE_FLAGS were set. You don't need both."
-        );
-    }
-
-    let path = Path::new(&input).join("features.toml");
-
-    let toml: HashMap<String, Feature> = toml::from_str(&std::fs::read_to_string(path)?)?;
-
-    for (key, value) in toml.iter() {
-        if value.enabled == true || all_on || flags.contains(key) {
-            println!("cargo:rustc-cfg={}", key);
-        }
-    }
-
-    Ok(())
+    nu_build::build()
 }

crates/nu-build/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "nu-build"
+version = "0.12.0"
+authors = ["Yehuda Katz <wycats@gmail.com>", "Jonathan Turner <jonathan.d.turner@gmail.com>", "Andrés N. Robalino <andres@androbtech.com>"]
+edition = "2018"
+description = "Core build system for nushell"
+license = "MIT"
+
+[lib]
+doctest = false
+
+[dependencies]
+serde = { version = "1.0.103", features = ["derive"] }
+lazy_static = "1.4.0"
+serde_json = "1.0.44"
+toml = "0.5.5"

crates/nu-build/src/lib.rs

@@ -0,0 +1,80 @@
+use lazy_static::lazy_static;
+use serde::Deserialize;
+use std::collections::BTreeMap;
+use std::collections::HashMap;
+use std::collections::HashSet;
+use std::env;
+use std::path::{Path, PathBuf};
+use std::sync::Mutex;
+
+lazy_static! {
+    static ref WORKSPACES: Mutex<BTreeMap<String, &'static Path>> = Mutex::new(BTreeMap::new());
+}
+
+// got from https://github.com/mitsuhiko/insta/blob/b113499249584cb650150d2d01ed96ee66db6b30/src/runtime.rs#L67-L88
+
+fn get_cargo_workspace(manifest_dir: &str) -> Result<Option<&Path>, Box<dyn std::error::Error>> {
+    let mut workspaces = WORKSPACES.lock()?;
+    if let Some(rv) = workspaces.get(manifest_dir) {
+        Ok(Some(rv))
+    } else {
+        #[derive(Deserialize)]
+        struct Manifest {
+            workspace_root: String,
+        }
+        let output = std::process::Command::new(env!("CARGO"))
+            .arg("metadata")
+            .arg("--format-version=1")
+            .current_dir(manifest_dir)
+            .output()?;
+        let manifest: Manifest = serde_json::from_slice(&output.stdout)?;
+        let path = Box::leak(Box::new(PathBuf::from(manifest.workspace_root)));
+        workspaces.insert(manifest_dir.to_string(), path.as_path());
+        Ok(workspaces.get(manifest_dir).cloned())
+    }
+}
+
+#[derive(Deserialize)]
+struct Feature {
+    #[allow(unused)]
+    description: String,
+    enabled: bool,
+}
+
+pub fn build() -> Result<(), Box<dyn std::error::Error>> {
+    let input = env::var("CARGO_MANIFEST_DIR")?;
+
+    let all_on = env::var("NUSHELL_ENABLE_ALL_FLAGS").is_ok();
+    let flags: HashSet<String> = env::var("NUSHELL_ENABLE_FLAGS")
+        .map(|s| s.split(',').map(|s| s.to_string()).collect())
+        .unwrap_or_else(|_| HashSet::new());
+
+    if all_on && !flags.is_empty() {
+        println!(
+            "cargo:warning=Both NUSHELL_ENABLE_ALL_FLAGS and NUSHELL_ENABLE_FLAGS were set. You don't need both."
+        );
+    }
+
+    let workspace = match get_cargo_workspace(&input)? {
+        // If the crate is being downloaded from crates.io, it won't have a workspace root, and that's ok
+        None => return Ok(()),
+        Some(workspace) => workspace,
+    };
+
+    let path = Path::new(&workspace).join("features.toml");
+
+    // If the crate is being downloaded from crates.io, it won't have a features.toml, and that's ok
+    if !path.exists() {
+        return Ok(());
+    }
+
+    let toml: HashMap<String, Feature> = toml::from_str(&std::fs::read_to_string(path)?)?;
+
+    for (key, value) in toml.iter() {
+        if value.enabled || all_on || flags.contains(key) {
+            println!("cargo:rustc-cfg={}", key);
+        }
+    }
+
+    Ok(())
+}

crates/nu-cli/Cargo.toml

@@ -0,0 +1,110 @@
+[package]
+name = "nu-cli"
+version = "0.12.0"
+authors = ["Yehuda Katz <wycats@gmail.com>", "Jonathan Turner <jonathan.d.turner@gmail.com>", "Andrés N. Robalino <andres@androbtech.com>"]
+description = "CLI for nushell"
+edition = "2018"
+license = "MIT"
+
+[lib]
+doctest = false
+
+[dependencies]
+nu-source = { version = "0.12.0", path = "../nu-source" }
+nu-plugin = { version = "0.12.0", path = "../nu-plugin" }
+nu-protocol = { version = "0.12.0", path = "../nu-protocol" }
+nu-errors = { version = "0.12.0", path = "../nu-errors" }
+nu-parser = { version = "0.12.0", path = "../nu-parser" }
+nu-value-ext = { version = "0.12.0", path = "../nu-value-ext" }
+nu-macros = { version = "0.12.0", path = "../nu-macros" }
+nu-test-support = { version = "0.12.0", path = "../nu-test-support" }
+
+ansi_term = "0.12.1"
+app_dirs = "1.2.1"
+async-stream = "0.2"
+base64 = "0.12.0"
+bigdecimal = { version = "0.1.0", features = ["serde"] }
+bson = { version = "0.14.1", features = ["decimal128"] }
+byte-unit = "3.0.3"
+bytes = "0.5.4"
+calamine = "0.16"
+cfg-if = "0.1"
+chrono = { version = "0.4.11", features = ["serde"] }
+clap = "2.33.0"
+csv = "1.1"
+ctrlc = "3.1.4"
+derive-new = "0.5.8"
+dirs = "2.0.2"
+dunce = "1.0.0"
+filesize = "0.1.0"
+futures = { version = "0.3", features = ["compat", "io-compat"] }
+futures-util = "0.3.4"
+futures_codec = "0.4"
+getset = "0.1.0"
+git2 = { version = "0.13.0", default_features = false }
+glob = "0.3.0"
+hex = "0.4"
+htmlescape = "0.3.1"
+ical = "0.6.*"
+ichwh = "0.3"
+indexmap = { version = "1.3.2", features = ["serde-1"] }
+itertools = "0.9.0"
+language-reporting = "0.4.0"
+log = "0.4.8"
+meval = "0.2"
+natural = "0.5.0"
+nom = "5.0.1"
+nom-tracable = "0.4.1"
+nom_locate = "1.0.0"
+num-bigint = { version = "0.2.6", features = ["serde"] }
+num-traits = "0.2.11"
+parking_lot = "0.10.0"
+pin-utils = "0.1.0-alpha.4"
+pretty-hex = "0.1.1"
+pretty_env_logger = "0.4.0"
+prettytable-rs = "0.8.0"
+ptree = {version = "0.2" }
+query_interface = "0.3.5"
+rand = "0.7"
+regex = "1"
+roxmltree = "0.10.0"
+rustyline = "6.0.0"
+serde = { version = "1.0.105", features = ["derive"] }
+serde-hjson = "0.9.1"
+serde_bytes = "0.11.3"
+serde_ini = "0.2.0"
+serde_json = "1.0.48"
+serde_urlencoded = "0.6.1"
+serde_yaml = "0.8"
+shellexpand = "2.0.0"
+strip-ansi-escapes = "0.1.0"
+tempfile = "3.1.0"
+term = "0.5.2"
+termcolor = "1.1.0"
+textwrap = {version = "0.11.0", features = ["term_size"]}
+toml = "0.5.6"
+trash = "1.0.0"
+typetag = "0.1.4"
+umask = "0.1"
+unicode-xid = "0.2.0"
+
+clipboard = { version = "0.5", optional = true }
+starship = { version = "0.38.0", optional = true }
+
+[target.'cfg(unix)'.dependencies]
+users = "0.9"
+
+[dependencies.rusqlite]
+version = "0.21.0"
+features = ["bundled", "blob"]
+
+[dev-dependencies]
+pretty_assertions = "0.6.1"
+
+[build-dependencies]
+nu-build = { version = "0.12.0", path = "../nu-build" }
+
+[features]
+stable = []
+starship-prompt = ["starship"]
+clipboard-cli = ["clipboard"]

crates/nu-cli/src/cli.rs

@@ -0,0 +1,800 @@
+use crate::commands::classified::external::{MaybeTextCodec, StringOrBinary};
+use crate::commands::classified::pipeline::run_pipeline;
+use crate::commands::plugin::JsonRpc;
+use crate::commands::plugin::{PluginCommand, PluginSink};
+use crate::commands::whole_stream_command;
+use crate::context::Context;
+#[cfg(not(feature = "starship-prompt"))]
+use crate::git::current_branch;
+use crate::prelude::*;
+use futures_codec::FramedRead;
+
+use nu_errors::ShellError;
+use nu_parser::{
+    ClassifiedCommand, ClassifiedPipeline, ExternalCommand, PipelineShape, SpannedToken,
+    TokensIterator,
+};
+use nu_protocol::{Primitive, ReturnSuccess, Signature, UntaggedValue, Value};
+
+use log::{debug, log_enabled, trace};
+use rustyline::error::ReadlineError;
+use rustyline::{
+    self, config::Configurer, config::EditMode, At, Cmd, ColorMode, CompletionType, Config, Editor,
+    KeyPress, Movement, Word,
+};
+use std::error::Error;
+use std::io::{BufRead, BufReader, Write};
+use std::iter::Iterator;
+use std::path::PathBuf;
+use std::sync::atomic::Ordering;
+
+fn load_plugin(path: &std::path::Path, context: &mut Context) -> Result<(), ShellError> {
+    let mut child = std::process::Command::new(path)
+        .stdin(std::process::Stdio::piped())
+        .stdout(std::process::Stdio::piped())
+        .spawn()
+        .expect("Failed to spawn child process");
+
+    let stdin = child.stdin.as_mut().expect("Failed to open stdin");
+    let stdout = child.stdout.as_mut().expect("Failed to open stdout");
+
+    let mut reader = BufReader::new(stdout);
+
+    let request = JsonRpc::new("config", Vec::<Value>::new());
+    let request_raw = serde_json::to_string(&request)?;
+    stdin.write_all(format!("{}\n", request_raw).as_bytes())?;
+    let path = dunce::canonicalize(path)?;
+
+    let mut input = String::new();
+    let result = match reader.read_line(&mut input) {
+        Ok(count) => {
+            trace!("processing response ({} bytes)", count);
+            trace!("response: {}", input);
+
+            let response = serde_json::from_str::<JsonRpc<Result<Signature, ShellError>>>(&input);
+            match response {
+                Ok(jrpc) => match jrpc.params {
+                    Ok(params) => {
+                        let fname = path.to_string_lossy();
+
+                        trace!("processing {:?}", params);
+
+                        let name = params.name.clone();
+                        let fname = fname.to_string();
+
+                        if context.get_command(&name).is_some() {
+                            trace!("plugin {:?} already loaded.", &name);
+                        } else if params.is_filter {
+                            context.add_commands(vec![whole_stream_command(PluginCommand::new(
+                                name, fname, params,
+                            ))]);
+                        } else {
+                            context.add_commands(vec![whole_stream_command(PluginSink::new(
+                                name, fname, params,
+                            ))]);
+                        }
+                        Ok(())
+                    }
+                    Err(e) => Err(e),
+                },
+                Err(e) => {
+                    trace!("incompatible plugin {:?}", input);
+                    Err(ShellError::untagged_runtime_error(format!(
+                        "Error: {:?}",
+                        e
+                    )))
+                }
+            }
+        }
+        Err(e) => Err(ShellError::untagged_runtime_error(format!(
+            "Error: {:?}",
+            e
+        ))),
+    };
+
+    let _ = child.wait();
+
+    result
+}
+
+fn search_paths() -> Vec<std::path::PathBuf> {
+    use std::env;
+
+    let mut search_paths = Vec::new();
+
+    // Automatically add path `nu` is in as a search path
+    if let Ok(exe_path) = env::current_exe() {
+        if let Some(exe_dir) = exe_path.parent() {
+            search_paths.push(exe_dir.to_path_buf());
+        }
+    }
+
+    #[cfg(not(debug_assertions))]
+    {
+        match env::var_os("PATH") {
+            Some(paths) => {
+                search_paths.extend(env::split_paths(&paths).collect::<Vec<_>>());
+            }
+            None => println!("PATH is not defined in the environment."),
+        }
+    }
+
+    search_paths
+}
+
+pub fn load_plugins(context: &mut Context) -> Result<(), ShellError> {
+    let opts = glob::MatchOptions {
+        case_sensitive: false,
+        require_literal_separator: false,
+        require_literal_leading_dot: false,
+    };
+
+    for path in search_paths() {
+        let mut pattern = path.to_path_buf();
+
+        pattern.push(std::path::Path::new("nu_plugin_[a-z0-9][a-z0-9]*"));
+
+        match glob::glob_with(&pattern.to_string_lossy(), opts) {
+            Err(_) => {}
+            Ok(binaries) => {
+                for bin in binaries.filter_map(Result::ok) {
+                    if !bin.is_file() {
+                        continue;
+                    }
+
+                    let bin_name = {
+                        if let Some(name) = bin.file_name() {
+                            match name.to_str() {
+                                Some(raw) => raw,
+                                None => continue,
+                            }
+                        } else {
+                            continue;
+                        }
+                    };
+
+                    let is_valid_name = {
+                        #[cfg(windows)]
+                        {
+                            bin_name
+                                .chars()
+                                .all(|c| c.is_ascii_alphanumeric() || c == '_' || c == '.')
+                        }
+
+                        #[cfg(not(windows))]
+                        {
+                            bin_name
+                                .chars()
+                                .all(|c| c.is_ascii_alphanumeric() || c == '_')
+                        }
+                    };
+
+                    let is_executable = {
+                        #[cfg(windows)]
+                        {
+                            bin_name.ends_with(".exe") || bin_name.ends_with(".bat")
+                        }
+
+                        #[cfg(not(windows))]
+                        {
+                            true
+                        }
+                    };
+
+                    if is_valid_name && is_executable {
+                        trace!("Trying {:?}", bin.display());
+
+                        // we are ok if this plugin load fails
+                        let _ = load_plugin(&bin, context);
+                    }
+                }
+            }
+        }
+    }
+
+    Ok(())
+}
+
+pub struct History;
+
+impl History {
+    pub fn path() -> PathBuf {
+        const FNAME: &str = "history.txt";
+        config::user_data()
+            .map(|mut p| {
+                p.push(FNAME);
+                p
+            })
+            .unwrap_or_else(|_| PathBuf::from(FNAME))
+    }
+}
+
+#[allow(dead_code)]
+fn create_default_starship_config() -> Option<toml::Value> {
+    let mut map = toml::value::Table::new();
+    map.insert("add_newline".into(), toml::Value::Boolean(false));
+
+    let mut git_branch = toml::value::Table::new();
+    git_branch.insert("symbol".into(), toml::Value::String("📙 ".into()));
+    map.insert("git_branch".into(), toml::Value::Table(git_branch));
+
+    let mut git_status = toml::value::Table::new();
+    git_status.insert("disabled".into(), toml::Value::Boolean(true));
+    map.insert("git_status".into(), toml::Value::Table(git_status));
+
+    Some(toml::Value::Table(map))
+}
+
+pub fn create_default_context(
+    syncer: &mut crate::env::environment_syncer::EnvironmentSyncer,
+) -> Result<Context, Box<dyn Error>> {
+    syncer.load_environment();
+
+    let mut context = Context::basic()?;
+    syncer.sync_env_vars(&mut context);
+    syncer.sync_path_vars(&mut context);
+
+    {
+        use crate::commands::*;
+
+        context.add_commands(vec![
+            // System/file operations
+            whole_stream_command(Pwd),
+            per_item_command(Ls),
+            per_item_command(Du),
+            whole_stream_command(Cd),
+            per_item_command(Remove),
+            per_item_command(Open),
+            whole_stream_command(Config),
+            per_item_command(Help),
+            per_item_command(History),
+            whole_stream_command(Save),
+            per_item_command(Touch),
+            per_item_command(Cpy),
+            whole_stream_command(Date),
+            per_item_command(Calc),
+            per_item_command(Mkdir),
+            per_item_command(Move),
+            per_item_command(Kill),
+            whole_stream_command(Version),
+            whole_stream_command(Clear),
+            whole_stream_command(What),
+            whole_stream_command(Which),
+            whole_stream_command(Debug),
+            // Statistics
+            whole_stream_command(Size),
+            whole_stream_command(Count),
+            // Metadata
+            whole_stream_command(Tags),
+            // Shells
+            whole_stream_command(Next),
+            whole_stream_command(Previous),
+            whole_stream_command(Shells),
+            per_item_command(Enter),
+            whole_stream_command(Exit),
+            // Viewers
+            whole_stream_command(Autoview),
+            whole_stream_command(Table),
+            // Text manipulation
+            whole_stream_command(SplitColumn),
+            whole_stream_command(SplitRow),
+            whole_stream_command(Lines),
+            whole_stream_command(Trim),
+            per_item_command(Echo),
+            per_item_command(Parse),
+            // Column manipulation
+            whole_stream_command(Reject),
+            whole_stream_command(Pick),
+            whole_stream_command(Get),
+            per_item_command(Edit),
+            per_item_command(Insert),
+            whole_stream_command(SplitBy),
+            // Row manipulation
+            whole_stream_command(Reverse),
+            whole_stream_command(Append),
+            whole_stream_command(Prepend),
+            whole_stream_command(SortBy),
+            whole_stream_command(GroupBy),
+            whole_stream_command(First),
+            whole_stream_command(Last),
+            whole_stream_command(Skip),
+            whole_stream_command(Nth),
+            per_item_command(Format),
+            per_item_command(Where),
+            whole_stream_command(Compact),
+            whole_stream_command(Default),
+            whole_stream_command(SkipWhile),
+            whole_stream_command(Range),
+            whole_stream_command(Rename),
+            whole_stream_command(Uniq),
+            // Table manipulation
+            whole_stream_command(Shuffle),
+            whole_stream_command(Wrap),
+            whole_stream_command(Pivot),
+            whole_stream_command(Headers),
+            // Data processing
+            whole_stream_command(Histogram),
+            whole_stream_command(Sum),
+            // File format output
+            whole_stream_command(ToBSON),
+            whole_stream_command(ToCSV),
+            whole_stream_command(ToHTML),
+            whole_stream_command(ToJSON),
+            whole_stream_command(ToSQLite),
+            whole_stream_command(ToDB),
+            whole_stream_command(ToMarkdown),
+            whole_stream_command(ToTOML),
+            whole_stream_command(ToTSV),
+            whole_stream_command(ToURL),
+            whole_stream_command(ToYAML),
+            // File format input
+            whole_stream_command(FromCSV),
+            whole_stream_command(FromTSV),
+            whole_stream_command(FromSSV),
+            whole_stream_command(FromINI),
+            whole_stream_command(FromBSON),
+            whole_stream_command(FromJSON),
+            whole_stream_command(FromODS),
+            whole_stream_command(FromDB),
+            whole_stream_command(FromSQLite),
+            whole_stream_command(FromTOML),
+            whole_stream_command(FromURL),
+            whole_stream_command(FromXLSX),
+            whole_stream_command(FromXML),
+            whole_stream_command(FromYAML),
+            whole_stream_command(FromYML),
+            whole_stream_command(FromIcs),
+            whole_stream_command(FromVcf),
+        ]);
+
+        cfg_if::cfg_if! {
+            if #[cfg(data_processing_primitives)] {
+                context.add_commands(vec![
+                whole_stream_command(ReduceBy),
+                whole_stream_command(EvaluateBy),
+                whole_stream_command(TSortBy),
+                whole_stream_command(MapMaxBy),
+                ]);
+            }
+        }
+
+        #[cfg(feature = "clipboard")]
+        {
+            context.add_commands(vec![whole_stream_command(
+                crate::commands::clip::clipboard::Clip,
+            )]);
+        }
+    }
+
+    Ok(context)
+}
+
+pub async fn run_pipeline_standalone(
+    pipeline: String,
+    redirect_stdin: bool,
+    context: &mut Context,
+) -> Result<(), Box<dyn Error>> {
+    let line = process_line(Ok(pipeline), context, redirect_stdin, false).await;
+
+    match line {
+        LineResult::Success(line) => {
+            let error_code = {
+                let errors = context.current_errors.clone();
+                let errors = errors.lock();
+
+                if errors.len() > 0 {
+                    1
+                } else {
+                    0
+                }
+            };
+
+            context.maybe_print_errors(Text::from(line));
+            if error_code != 0 {
+                std::process::exit(error_code);
+            }
+        }
+
+        LineResult::Error(line, err) => {
+            context.with_host(|host| {
+                print_err(err, host, &Text::from(line.clone()));
+            });
+
+            context.maybe_print_errors(Text::from(line));
+            std::process::exit(1);
+        }
+
+        _ => {}
+    }
+
+    Ok(())
+}
+
+/// The entry point for the CLI. Will register all known internal commands, load experimental commands, load plugins, then prepare the prompt and line reader for input.
+pub async fn cli() -> Result<(), Box<dyn Error>> {
+    let mut syncer = crate::env::environment_syncer::EnvironmentSyncer::new();
+    let mut context = create_default_context(&mut syncer)?;
+
+    let _ = load_plugins(&mut context);
+
+    let config = Config::builder().color_mode(ColorMode::Forced).build();
+    let mut rl: Editor<_> = Editor::with_config(config);
+
+    // add key bindings to move over a whole word with Ctrl+ArrowLeft and Ctrl+ArrowRight
+    rl.bind_sequence(
+        KeyPress::ControlLeft,
+        Cmd::Move(Movement::BackwardWord(1, Word::Vi)),
+    );
+    rl.bind_sequence(
+        KeyPress::ControlRight,
+        Cmd::Move(Movement::ForwardWord(1, At::AfterEnd, Word::Vi)),
+    );
+
+    #[cfg(windows)]
+    {
+        let _ = ansi_term::enable_ansi_support();
+    }
+
+    // we are ok if history does not exist
+    let _ = rl.load_history(&History::path());
+
+    let cc = context.ctrl_c.clone();
+    ctrlc::set_handler(move || {
+        cc.store(true, Ordering::SeqCst);
+    })
+    .expect("Error setting Ctrl-C handler");
+    let mut ctrlcbreak = false;
+    loop {
+        if context.ctrl_c.load(Ordering::SeqCst) {
+            context.ctrl_c.store(false, Ordering::SeqCst);
+            continue;
+        }
+
+        let cwd = context.shell_manager.path();
+
+        rl.set_helper(Some(crate::shell::Helper::new(context.clone())));
+
+        let edit_mode = config::config(Tag::unknown())?
+            .get("edit_mode")
+            .map(|s| match s.value.expect_string() {
+                "vi" => EditMode::Vi,
+                "emacs" => EditMode::Emacs,
+                _ => EditMode::Emacs,
+            })
+            .unwrap_or(EditMode::Emacs);
+
+        rl.set_edit_mode(edit_mode);
+
+        let completion_mode = config::config(Tag::unknown())?
+            .get("completion_mode")
+            .map(|s| match s.value.expect_string() {
+                "list" => CompletionType::List,
+                "circular" => CompletionType::Circular,
+                _ => CompletionType::Circular,
+            })
+            .unwrap_or(CompletionType::Circular);
+
+        rl.set_completion_type(completion_mode);
+
+        let colored_prompt = {
+            #[cfg(feature = "starship-prompt")]
+            {
+                std::env::set_var("STARSHIP_SHELL", "");
+                let mut starship_context =
+                    starship::context::Context::new_with_dir(clap::ArgMatches::default(), cwd);
+
+                match starship_context.config.config {
+                    None => {
+                        starship_context.config.config = create_default_starship_config();
+                    }
+                    Some(toml::Value::Table(t)) if t.is_empty() => {
+                        starship_context.config.config = create_default_starship_config();
+                    }
+                    _ => {}
+                };
+                starship::print::get_prompt(starship_context)
+            }
+            #[cfg(not(feature = "starship-prompt"))]
+            {
+                format!(
+                    "\x1b[32m{}{}\x1b[m> ",
+                    cwd,
+                    match current_branch() {
+                        Some(s) => format!("({})", s),
+                        None => "".to_string(),
+                    }
+                )
+            }
+        };
+
+        let prompt = {
+            if let Ok(bytes) = strip_ansi_escapes::strip(&colored_prompt) {
+                String::from_utf8_lossy(&bytes).to_string()
+            } else {
+                "> ".to_string()
+            }
+        };
+
+        rl.helper_mut().expect("No helper").colored_prompt = colored_prompt;
+        let mut initial_command = Some(String::new());
+        let mut readline = Err(ReadlineError::Eof);
+        while let Some(ref cmd) = initial_command {
+            readline = rl.readline_with_initial(&prompt, (&cmd, ""));
+            initial_command = None;
+        }
+
+        let line = process_line(readline, &mut context, false, true).await;
+
+        // Check the config to see if we need to update the path
+        // TODO: make sure config is cached so we don't path this load every call
+        // FIXME: we probably want to be a bit more graceful if we can't set the environment
+        syncer.reload();
+        syncer.sync_env_vars(&mut context);
+        syncer.sync_path_vars(&mut context);
+
+        match line {
+            LineResult::Success(line) => {
+                rl.add_history_entry(line.clone());
+                let _ = rl.save_history(&History::path());
+                context.maybe_print_errors(Text::from(line));
+            }
+
+            LineResult::Error(line, err) => {
+                rl.add_history_entry(line.clone());
+                let _ = rl.save_history(&History::path());
+
+                context.with_host(|host| {
+                    print_err(err, host, &Text::from(line.clone()));
+                });
+
+                context.maybe_print_errors(Text::from(line.clone()));
+            }
+
+            LineResult::CtrlC => {
+                let config_ctrlc_exit = config::config(Tag::unknown())?
+                    .get("ctrlc_exit")
+                    .map(|s| match s.value.expect_string() {
+                        "true" => true,
+                        _ => false,
+                    })
+                    .unwrap_or(false); // default behavior is to allow CTRL-C spamming similar to other shells
+
+                if !config_ctrlc_exit {
+                    continue;
+                }
+
+                if ctrlcbreak {
+                    let _ = rl.save_history(&History::path());
+                    std::process::exit(0);
+                } else {
+                    context.with_host(|host| host.stdout("CTRL-C pressed (again to quit)"));
+                    ctrlcbreak = true;
+                    continue;
+                }
+            }
+
+            LineResult::Break => {
+                break;
+            }
+        }
+        ctrlcbreak = false;
+    }
+
+    // we are ok if we can not save history
+    let _ = rl.save_history(&History::path());
+
+    Ok(())
+}
+
+fn chomp_newline(s: &str) -> &str {
+    if s.ends_with('\n') {
+        &s[..s.len() - 1]
+    } else {
+        s
+    }
+}
+
+enum LineResult {
+    Success(String),
+    Error(String, ShellError),
+    CtrlC,
+    Break,
+}
+
+/// Process the line by parsing the text to turn it into commands, classify those commands so that we understand what is being called in the pipeline, and then run this pipeline
+async fn process_line(
+    readline: Result<String, ReadlineError>,
+    ctx: &mut Context,
+    redirect_stdin: bool,
+    cli_mode: bool,
+) -> LineResult {
+    match &readline {
+        Ok(line) if line.trim() == "" => LineResult::Success(line.clone()),
+
+        Ok(line) => {
+            let line = chomp_newline(line);
+
+            let result = match nu_parser::parse(&line) {
+                Err(err) => {
+                    return LineResult::Error(line.to_string(), err);
+                }
+
+                Ok(val) => val,
+            };
+
+            debug!("=== Parsed ===");
+            debug!("{:#?}", result);
+
+            let pipeline = classify_pipeline(&result, &ctx, &Text::from(line));
+
+            if let Some(failure) = pipeline.failed {
+                return LineResult::Error(line.to_string(), failure.into());
+            }
+
+            // There's a special case to check before we process the pipeline:
+            // If we're giving a path by itself
+            // ...and it's not a command in the path
+            // ...and it doesn't have any arguments
+            // ...and we're in the CLI
+            // ...then change to this directory
+            if cli_mode && pipeline.commands.list.len() == 1 {
+                if let ClassifiedCommand::External(ExternalCommand {
+                    ref name, ref args, ..
+                }) = pipeline.commands.list[0]
+                {
+                    if dunce::canonicalize(name).is_ok()
+                        && PathBuf::from(name).is_dir()
+                        && ichwh::which(name).await.unwrap_or(None).is_none()
+                        && args.list.is_empty()
+                    {
+                        // Here we work differently if we're in Windows because of the expected Windows behavior
+                        #[cfg(windows)]
+                        {
+                            if name.ends_with(':') {
+                                // This looks like a drive shortcut. We need to a) switch drives and b) go back to the previous directory we were viewing on that drive
+                                // But first, we need to save where we are now
+                                let current_path = ctx.shell_manager.path();
+
+                                let split_path: Vec<_> = current_path.split(':').collect();
+                                if split_path.len() > 1 {
+                                    ctx.windows_drives_previous_cwd
+                                        .lock()
+                                        .insert(split_path[0].to_string(), current_path);
+                                }
+
+                                let name = name.to_uppercase();
+                                let new_drive: Vec<_> = name.split(':').collect();
+
+                                if let Some(val) =
+                                    ctx.windows_drives_previous_cwd.lock().get(new_drive[0])
+                                {
+                                    ctx.shell_manager.set_path(val.to_string());
+                                    return LineResult::Success(line.to_string());
+                                } else {
+                                    ctx.shell_manager.set_path(name.to_string());
+                                    return LineResult::Success(line.to_string());
+                                }
+                            } else {
+                                ctx.shell_manager.set_path(name.to_string());
+                                return LineResult::Success(line.to_string());
+                            }
+                        }
+                        #[cfg(not(windows))]
+                        {
+                            ctx.shell_manager.set_path(name.to_string());
+                            return LineResult::Success(line.to_string());
+                        }
+                    }
+                }
+            }
+            let input_stream = if redirect_stdin {
+                let file = futures::io::AllowStdIo::new(std::io::stdin());
+                let stream = FramedRead::new(file, MaybeTextCodec).map(|line| {
+                    if let Ok(line) = line {
+                        match line {
+                            StringOrBinary::String(s) => Ok(Value {
+                                value: UntaggedValue::Primitive(Primitive::String(s)),
+                                tag: Tag::unknown(),
+                            }),
+                            StringOrBinary::Binary(b) => Ok(Value {
+                                value: UntaggedValue::Primitive(Primitive::Binary(
+                                    b.into_iter().collect(),
+                                )),
+                                tag: Tag::unknown(),
+                            }),
+                        }
+                    } else {
+                        panic!("Internal error: could not read lines of text from stdin")
+                    }
+                });
+                Some(stream.to_input_stream())
+            } else {
+                None
+            };
+
+            match run_pipeline(pipeline, ctx, input_stream, line).await {
+                Ok(Some(input)) => {
+                    // Running a pipeline gives us back a stream that we can then
+                    // work through. At the top level, we just want to pull on the
+                    // values to compute them.
+                    use futures::stream::TryStreamExt;
+
+                    let context = RunnableContext {
+                        input,
+                        shell_manager: ctx.shell_manager.clone(),
+                        host: ctx.host.clone(),
+                        ctrl_c: ctx.ctrl_c.clone(),
+                        commands: ctx.registry.clone(),
+                        name: Tag::unknown(),
+                        source: Text::from(String::new()),
+                    };
+
+                    if let Ok(mut output_stream) = crate::commands::autoview::autoview(context) {
+                        loop {
+                            match output_stream.try_next().await {
+                                Ok(Some(ReturnSuccess::Value(Value {
+                                    value: UntaggedValue::Error(e),
+                                    ..
+                                }))) => return LineResult::Error(line.to_string(), e),
+                                Ok(Some(_item)) => {
+                                    if ctx.ctrl_c.load(Ordering::SeqCst) {
+                                        break;
+                                    }
+                                }
+                                Ok(None) => break,
+                                Err(e) => return LineResult::Error(line.to_string(), e),
+                            }
+                        }
+                    }
+
+                    LineResult::Success(line.to_string())
+                }
+                Ok(None) => LineResult::Success(line.to_string()),
+                Err(err) => LineResult::Error(line.to_string(), err),
+            }
+        }
+        Err(ReadlineError::Interrupted) => LineResult::CtrlC,
+        Err(ReadlineError::Eof) => LineResult::Break,
+        Err(err) => {
+            outln!("Error: {:?}", err);
+            LineResult::Break
+        }
+    }
+}
+
+pub fn classify_pipeline(
+    pipeline: &SpannedToken,
+    context: &Context,
+    source: &Text,
+) -> ClassifiedPipeline {
+    let pipeline_list = vec![pipeline.clone()];
+    let expand_context = context.expand_context(source);
+    let mut iterator = TokensIterator::new(&pipeline_list, expand_context, pipeline.span());
+
+    let result = iterator.expand_infallible(PipelineShape);
+
+    if log_enabled!(target: "nu::expand_syntax", log::Level::Debug) {
+        outln!("");
+        let _ = ptree::print_tree(&iterator.expand_tracer().print(source.clone()));
+        outln!("");
+    }
+
+    result
+}
+
+pub fn print_err(err: ShellError, host: &dyn Host, source: &Text) {
+    let diag = err.into_diagnostic();
+
+    let writer = host.err_termcolor();
+    let mut source = source.to_string();
+    source.push_str(" ");
+    let files = nu_parser::Files::new(source);
+    let _ = std::panic::catch_unwind(move || {
+        let _ = language_reporting::emit(
+            &mut writer.lock(),
+            &files,
+            &diag,
+            &language_reporting::DefaultConfig,
+        );
+    });
+}

crates/nu-cli/src/commands.rs

@@ -1,144 +1,220 @@
 #[macro_use]
 pub(crate) mod macros;
 
+mod from_delimited_data;
+mod to_delimited_data;
+
+pub(crate) mod append;
 pub(crate) mod args;
 pub(crate) mod autoview;
+pub(crate) mod calc;
 pub(crate) mod cd;
 pub(crate) mod classified;
 pub(crate) mod clip;
 pub(crate) mod command;
+pub(crate) mod compact;
 pub(crate) mod config;
 pub(crate) mod count;
 pub(crate) mod cp;
 pub(crate) mod date;
 pub(crate) mod debug;
+pub(crate) mod default;
+pub(crate) mod du;
 pub(crate) mod echo;
+pub(crate) mod edit;
 pub(crate) mod enter;
-pub(crate) mod env;
+#[allow(unused)]
+pub(crate) mod evaluate_by;
 pub(crate) mod exit;
-pub(crate) mod fetch;
 pub(crate) mod first;
+pub(crate) mod format;
 pub(crate) mod from_bson;
 pub(crate) mod from_csv;
+pub(crate) mod from_ics;
 pub(crate) mod from_ini;
 pub(crate) mod from_json;
+pub(crate) mod from_ods;
 pub(crate) mod from_sqlite;
 pub(crate) mod from_ssv;
 pub(crate) mod from_toml;
 pub(crate) mod from_tsv;
 pub(crate) mod from_url;
+pub(crate) mod from_vcf;
+pub(crate) mod from_xlsx;
 pub(crate) mod from_xml;
 pub(crate) mod from_yaml;
 pub(crate) mod get;
+pub(crate) mod group_by;
+pub(crate) mod headers;
 pub(crate) mod help;
+pub(crate) mod histogram;
+pub(crate) mod history;
+pub(crate) mod insert;
 pub(crate) mod last;
 pub(crate) mod lines;
 pub(crate) mod ls;
+#[allow(unused)]
+pub(crate) mod map_max_by;
 pub(crate) mod mkdir;
 pub(crate) mod mv;
 pub(crate) mod next;
 pub(crate) mod nth;
 pub(crate) mod open;
+pub(crate) mod parse;
 pub(crate) mod pick;
 pub(crate) mod pivot;
 pub(crate) mod plugin;
-pub(crate) mod post;
+pub(crate) mod prepend;
 pub(crate) mod prev;
 pub(crate) mod pwd;
+pub(crate) mod range;
+#[allow(unused)]
+pub(crate) mod reduce_by;
 pub(crate) mod reject;
+pub(crate) mod rename;
 pub(crate) mod reverse;
 pub(crate) mod rm;
 pub(crate) mod save;
 pub(crate) mod shells;
+pub(crate) mod shuffle;
 pub(crate) mod size;
+pub(crate) mod skip;
 pub(crate) mod skip_while;
 pub(crate) mod sort_by;
+pub(crate) mod split_by;
 pub(crate) mod split_column;
 pub(crate) mod split_row;
+pub(crate) mod sum;
+#[allow(unused)]
+pub(crate) mod t_sort_by;
 pub(crate) mod table;
 pub(crate) mod tags;
 pub(crate) mod to_bson;
 pub(crate) mod to_csv;
+pub(crate) mod to_html;
 pub(crate) mod to_json;
+pub(crate) mod to_md;
 pub(crate) mod to_sqlite;
 pub(crate) mod to_toml;
 pub(crate) mod to_tsv;
 pub(crate) mod to_url;
 pub(crate) mod to_yaml;
 pub(crate) mod trim;
+pub(crate) mod uniq;
 pub(crate) mod version;
+pub(crate) mod what;
 pub(crate) mod where_;
 pub(crate) mod which_;
+pub(crate) mod wrap;
 
 pub(crate) use autoview::Autoview;
-pub(crate) use cd::CD;
+pub(crate) use cd::Cd;
 pub(crate) use command::{
-    per_item_command, whole_stream_command, Command, PerItemCommand, RawCommandArgs,
-    UnevaluatedCallInfo, WholeStreamCommand,
+    per_item_command, whole_stream_command, Command, PerItemCommand, UnevaluatedCallInfo,
+    WholeStreamCommand,
 };
 
-pub(crate) use classified::ClassifiedCommand;
+pub(crate) use append::Append;
+pub(crate) use calc::Calc;
+pub(crate) use compact::Compact;
 pub(crate) use config::Config;
 pub(crate) use count::Count;
 pub(crate) use cp::Cpy;
 pub(crate) use date::Date;
 pub(crate) use debug::Debug;
+pub(crate) use default::Default;
+pub(crate) use du::Du;
 pub(crate) use echo::Echo;
+pub(crate) use edit::Edit;
+pub(crate) mod kill;
+pub(crate) use kill::Kill;
+pub(crate) mod clear;
+pub(crate) use clear::Clear;
+pub(crate) mod touch;
 pub(crate) use enter::Enter;
-pub(crate) use env::Env;
+#[allow(unused_imports)]
+pub(crate) use evaluate_by::EvaluateBy;
 pub(crate) use exit::Exit;
-pub(crate) use fetch::Fetch;
 pub(crate) use first::First;
+pub(crate) use format::Format;
 pub(crate) use from_bson::FromBSON;
 pub(crate) use from_csv::FromCSV;
+pub(crate) use from_ics::FromIcs;
 pub(crate) use from_ini::FromINI;
 pub(crate) use from_json::FromJSON;
+pub(crate) use from_ods::FromODS;
 pub(crate) use from_sqlite::FromDB;
 pub(crate) use from_sqlite::FromSQLite;
 pub(crate) use from_ssv::FromSSV;
 pub(crate) use from_toml::FromTOML;
 pub(crate) use from_tsv::FromTSV;
 pub(crate) use from_url::FromURL;
+pub(crate) use from_vcf::FromVcf;
+pub(crate) use from_xlsx::FromXLSX;
 pub(crate) use from_xml::FromXML;
 pub(crate) use from_yaml::FromYAML;
 pub(crate) use from_yaml::FromYML;
 pub(crate) use get::Get;
+pub(crate) use group_by::GroupBy;
+pub(crate) use headers::Headers;
 pub(crate) use help::Help;
+pub(crate) use histogram::Histogram;
+pub(crate) use history::History;
+pub(crate) use insert::Insert;
 pub(crate) use last::Last;
 pub(crate) use lines::Lines;
-pub(crate) use ls::LS;
+pub(crate) use ls::Ls;
+#[allow(unused_imports)]
+pub(crate) use map_max_by::MapMaxBy;
 pub(crate) use mkdir::Mkdir;
 pub(crate) use mv::Move;
 pub(crate) use next::Next;
 pub(crate) use nth::Nth;
 pub(crate) use open::Open;
+pub(crate) use parse::Parse;
 pub(crate) use pick::Pick;
 pub(crate) use pivot::Pivot;
-pub(crate) use post::Post;
+pub(crate) use prepend::Prepend;
 pub(crate) use prev::Previous;
-pub(crate) use pwd::PWD;
+pub(crate) use pwd::Pwd;
+pub(crate) use range::Range;
+#[allow(unused_imports)]
+pub(crate) use reduce_by::ReduceBy;
 pub(crate) use reject::Reject;
+pub(crate) use rename::Rename;
 pub(crate) use reverse::Reverse;
 pub(crate) use rm::Remove;
 pub(crate) use save::Save;
 pub(crate) use shells::Shells;
+pub(crate) use shuffle::Shuffle;
 pub(crate) use size::Size;
+pub(crate) use skip::Skip;
 pub(crate) use skip_while::SkipWhile;
 pub(crate) use sort_by::SortBy;
+pub(crate) use split_by::SplitBy;
 pub(crate) use split_column::SplitColumn;
 pub(crate) use split_row::SplitRow;
+pub(crate) use sum::Sum;
+#[allow(unused_imports)]
+pub(crate) use t_sort_by::TSortBy;
 pub(crate) use table::Table;
 pub(crate) use tags::Tags;
 pub(crate) use to_bson::ToBSON;
 pub(crate) use to_csv::ToCSV;
+pub(crate) use to_html::ToHTML;
 pub(crate) use to_json::ToJSON;
+pub(crate) use to_md::ToMarkdown;
 pub(crate) use to_sqlite::ToDB;
 pub(crate) use to_sqlite::ToSQLite;
 pub(crate) use to_toml::ToTOML;
 pub(crate) use to_tsv::ToTSV;
 pub(crate) use to_url::ToURL;
 pub(crate) use to_yaml::ToYAML;
+pub(crate) use touch::Touch;
 pub(crate) use trim::Trim;
+pub(crate) use uniq::Uniq;
 pub(crate) use version::Version;
+pub(crate) use what::What;
 pub(crate) use where_::Where;
 pub(crate) use which_::Which;
+pub(crate) use wrap::Wrap;

crates/nu-cli/src/commands/append.rs

@@ -0,0 +1,49 @@
+use crate::commands::WholeStreamCommand;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Signature, SyntaxShape, Value};
+
+#[derive(Deserialize)]
+struct AppendArgs {
+    row: Value,
+}
+
+pub struct Append;
+
+impl WholeStreamCommand for Append {
+    fn name(&self) -> &str {
+        "append"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("append").required(
+            "row value",
+            SyntaxShape::Any,
+            "the value of the row to append to the table",
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Append the given row to the table"
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, append)?.run()
+    }
+}
+
+fn append(
+    AppendArgs { row }: AppendArgs,
+    RunnableContext { input, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let mut after: VecDeque<Value> = VecDeque::new();
+    after.push_back(row);
+    let after = futures::stream::iter(after);
+
+    Ok(OutputStream::from_input(input.values.chain(after)))
+}

crates/nu-cli/src/commands/args.rs

@@ -1,4 +1,4 @@
-use crate::data::Value;
+use nu_protocol::Value;
 
 #[derive(Debug)]
 pub enum LogLevel {}

crates/nu-cli/src/commands/autoview.rs

@@ -0,0 +1,296 @@
+use crate::commands::UnevaluatedCallInfo;
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_parser::{hir, hir::Expression, hir::Literal, hir::SpannedExpression};
+use nu_protocol::{Primitive, ReturnSuccess, Signature, UntaggedValue, Value};
+use std::sync::atomic::AtomicBool;
+use std::sync::atomic::Ordering;
+
+pub struct Autoview;
+
+impl WholeStreamCommand for Autoview {
+    fn name(&self) -> &str {
+        "autoview"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("autoview")
+    }
+
+    fn usage(&self) -> &str {
+        "View the contents of the pipeline as a table or list."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        autoview(RunnableContext {
+            input: args.input,
+            commands: registry.clone(),
+            shell_manager: args.shell_manager,
+            host: args.host,
+            source: args.call_info.source,
+            ctrl_c: args.ctrl_c,
+            name: args.call_info.name_tag,
+        })
+    }
+}
+
+pub struct RunnableContextWithoutInput {
+    pub shell_manager: ShellManager,
+    pub host: Arc<parking_lot::Mutex<Box<dyn Host>>>,
+    pub source: Text,
+    pub ctrl_c: Arc<AtomicBool>,
+    pub commands: CommandRegistry,
+    pub name: Tag,
+}
+
+impl RunnableContextWithoutInput {
+    pub fn convert(context: RunnableContext) -> (InputStream, RunnableContextWithoutInput) {
+        let new_context = RunnableContextWithoutInput {
+            shell_manager: context.shell_manager,
+            host: context.host,
+            source: context.source,
+            ctrl_c: context.ctrl_c,
+            commands: context.commands,
+            name: context.name,
+        };
+        (context.input, new_context)
+    }
+}
+
+pub fn autoview(context: RunnableContext) -> Result<OutputStream, ShellError> {
+    let binary = context.get_command("binaryview");
+    let text = context.get_command("textview");
+    let table = context.get_command("table");
+
+    Ok(OutputStream::new(async_stream! {
+        let (mut input_stream, context) = RunnableContextWithoutInput::convert(context);
+
+        match input_stream.next().await {
+            Some(x) => {
+                match input_stream.next().await {
+                    Some(y) => {
+                        let ctrl_c = context.ctrl_c.clone();
+                        let stream = async_stream! {
+                            yield Ok(x);
+                            yield Ok(y);
+
+                            loop {
+                                match input_stream.next().await {
+                                    Some(z) => {
+                                        if ctrl_c.load(Ordering::SeqCst) {
+                                            break;
+                                        }
+                                        yield Ok(z);
+                                    }
+                                    _ => break,
+                                }
+                            }
+                        };
+                        let stream = stream.to_input_stream();
+
+                        if let Some(table) = table {
+                            let command_args = create_default_command_args(&context).with_input(stream);
+                            let result = table.run(command_args, &context.commands);
+                            result.collect::<Vec<_>>().await;
+                        }
+                    }
+                    _ => {
+                        match x {
+                            Value {
+                                value: UntaggedValue::Primitive(Primitive::String(ref s)),
+                                tag: Tag { anchor, span },
+                            } if anchor.is_some() => {
+                                if let Some(text) = text {
+                                    let mut stream = VecDeque::new();
+                                    stream.push_back(UntaggedValue::string(s).into_value(Tag { anchor, span }));
+                                    let command_args = create_default_command_args(&context).with_input(stream);
+                                    let result = text.run(command_args, &context.commands);
+                                    result.collect::<Vec<_>>().await;
+                                } else {
+                                    out!("{}", s);
+                                }
+                            }
+                            Value {
+                                value: UntaggedValue::Primitive(Primitive::String(s)),
+                                ..
+                            } => {
+                                out!("{}", s);
+                            }
+                            Value {
+                                value: UntaggedValue::Primitive(Primitive::Line(ref s)),
+                                tag: Tag { anchor, span },
+                            } if anchor.is_some() => {
+                                if let Some(text) = text {
+                                    let mut stream = VecDeque::new();
+                                    stream.push_back(UntaggedValue::string(s).into_value(Tag { anchor, span }));
+                                    let command_args = create_default_command_args(&context).with_input(stream);
+                                    let result = text.run(command_args, &context.commands);
+                                    result.collect::<Vec<_>>().await;
+                                } else {
+                                    out!("{}\n", s);
+                                }
+                            }
+                            Value {
+                                value: UntaggedValue::Primitive(Primitive::Line(s)),
+                                ..
+                            } => {
+                                out!("{}\n", s);
+                            }
+                            Value {
+                                value: UntaggedValue::Primitive(Primitive::Path(s)),
+                                ..
+                            } => {
+                                out!("{}", s.display());
+                            }
+                            Value {
+                                value: UntaggedValue::Primitive(Primitive::Int(n)),
+                                ..
+                            } => {
+                                out!("{}", n);
+                            }
+                            Value {
+                                value: UntaggedValue::Primitive(Primitive::Decimal(n)),
+                                ..
+                            } => {
+                                out!("{}", n);
+                            }
+
+                            Value { value: UntaggedValue::Primitive(Primitive::Binary(ref b)), .. } => {
+                                if let Some(binary) = binary {
+                                    let mut stream = VecDeque::new();
+                                    stream.push_back(x);
+                                    let command_args = create_default_command_args(&context).with_input(stream);
+                                    let result = binary.run(command_args, &context.commands);
+                                    result.collect::<Vec<_>>().await;
+                                } else {
+                                    use pretty_hex::*;
+                                    out!("{:?}", b.hex_dump());
+                                }
+                            }
+
+                            Value { value: UntaggedValue::Error(e), .. } => {
+                                yield Err(e);
+                            }
+
+                            Value { value: UntaggedValue::Row(row), ..} => {
+                                use prettytable::format::{FormatBuilder, LinePosition, LineSeparator};
+                                use prettytable::{color, Attr, Cell, Row, Table};
+                                use crate::data::value::{format_leaf, style_leaf};
+                                use textwrap::fill;
+
+                                let termwidth = std::cmp::max(textwrap::termwidth(), 20);
+
+                                enum TableMode {
+                                    Light,
+                                    Normal,
+                                }
+
+                                let mut table = Table::new();
+                                let table_mode = crate::data::config::config(Tag::unknown());
+
+                                let table_mode = if let Some(s) = table_mode?.get("table_mode") {
+                                    match s.as_string() {
+                                        Ok(typ) if typ == "light" => TableMode::Light,
+                                        _ => TableMode::Normal,
+                                    }
+                                } else {
+                                    TableMode::Normal
+                                };
+
+                                match table_mode {
+                                    TableMode::Light => {
+                                        table.set_format(
+                                            FormatBuilder::new()
+                                                .separator(LinePosition::Title, LineSeparator::new('─', '─', ' ', ' '))
+                                                .padding(1, 1)
+                                                .build(),
+                                        );
+                                    }
+                                    _ => {
+                                        table.set_format(
+                                            FormatBuilder::new()
+                                                .column_separator('│')
+                                                .separator(LinePosition::Top, LineSeparator::new('─', '┬', ' ', ' '))
+                                                .separator(LinePosition::Title, LineSeparator::new('─', '┼', ' ', ' '))
+                                                .separator(LinePosition::Bottom, LineSeparator::new('─', '┴', ' ', ' '))
+                                                .padding(1, 1)
+                                                .build(),
+                                        );
+                                    }
+                                }
+
+                                let mut max_key_len = 0;
+                                for (key, _) in row.entries.iter() {
+                                    max_key_len = std::cmp::max(max_key_len, key.chars().count());
+                                }
+
+                                if max_key_len > (termwidth/2 - 1) {
+                                    max_key_len = termwidth/2 - 1;
+                                }
+
+                                let max_val_len = termwidth - max_key_len - 5;
+
+                                for (key, value) in row.entries.iter() {
+                                    table.add_row(Row::new(vec![Cell::new(&fill(&key, max_key_len)).with_style(Attr::ForegroundColor(color::GREEN)).with_style(Attr::Bold),
+                                        Cell::new(&fill(&format_leaf(value).plain_string(100_000), max_val_len))]));
+                                }
+
+                                table.printstd();
+
+                                // table.print_term(&mut *context.host.lock().out_terminal().ok_or_else(|| ShellError::untagged_runtime_error("Could not open terminal for output"))?)
+                                //     .map_err(|_| ShellError::untagged_runtime_error("Internal error: could not print to terminal (for unix systems check to make sure TERM is set)"))?;
+                            }
+
+                            Value { value: ref item, .. } => {
+                                if let Some(table) = table {
+                                    let mut stream = VecDeque::new();
+                                    stream.push_back(x);
+                                    let command_args = create_default_command_args(&context).with_input(stream);
+                                    let result = table.run(command_args, &context.commands);
+                                    result.collect::<Vec<_>>().await;
+                                } else {
+                                    out!("{:?}", item);
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+            _ => {
+                //out!("<no results>");
+            }
+        }
+
+        // Needed for async_stream to type check
+        if false {
+            yield ReturnSuccess::value(UntaggedValue::nothing().into_untagged_value());
+        }
+    }))
+}
+
+fn create_default_command_args(context: &RunnableContextWithoutInput) -> RawCommandArgs {
+    let span = context.name.span;
+    RawCommandArgs {
+        host: context.host.clone(),
+        ctrl_c: context.ctrl_c.clone(),
+        shell_manager: context.shell_manager.clone(),
+        call_info: UnevaluatedCallInfo {
+            args: hir::Call {
+                head: Box::new(SpannedExpression::new(
+                    Expression::Literal(Literal::String(span)),
+                    span,
+                )),
+                positional: None,
+                named: None,
+                span,
+            },
+            source: context.source.clone(),
+            name_tag: context.name.clone(),
+        },
+    }
+}

crates/nu-cli/src/commands/calc.rs

@@ -0,0 +1,63 @@
+use crate::commands::PerItemCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CallInfo, Primitive, ReturnSuccess, UntaggedValue, Value};
+
+pub struct Calc;
+
+impl PerItemCommand for Calc {
+    fn name(&self) -> &str {
+        "calc"
+    }
+
+    fn usage(&self) -> &str {
+        "Parse a math expression into a number"
+    }
+
+    fn run(
+        &self,
+        _call_info: &CallInfo,
+        _registry: &CommandRegistry,
+        raw_args: &RawCommandArgs,
+        input: Value,
+    ) -> Result<OutputStream, ShellError> {
+        calc(input, raw_args)
+    }
+}
+
+fn calc(input: Value, args: &RawCommandArgs) -> Result<OutputStream, ShellError> {
+    let name_span = &args.call_info.name_tag.span;
+
+    let output = if let Ok(string) = input.as_string() {
+        match parse(&string, &input.tag) {
+            Ok(value) => ReturnSuccess::value(value),
+            Err(err) => Err(ShellError::labeled_error(
+                "Calculation error",
+                err,
+                &input.tag.span,
+            )),
+        }
+    } else {
+        Err(ShellError::labeled_error(
+            "Expected a string from pipeline",
+            "requires string input",
+            name_span,
+        ))
+    };
+
+    Ok(vec![output].into())
+}
+
+pub fn parse(math_expression: &str, tag: impl Into<Tag>) -> Result<Value, String> {
+    use std::f64;
+    let num = meval::eval_str(math_expression);
+    match num {
+        Ok(num) => {
+            if num == f64::INFINITY || num == f64::NEG_INFINITY {
+                return Err(String::from("cannot represent result"));
+            }
+            Ok(UntaggedValue::from(Primitive::from(num)).into_value(tag))
+        }
+        Err(error) => Err(error.to_string()),
+    }
+}

crates/nu-cli/src/commands/cd.rs

@@ -1,16 +1,28 @@
 use crate::commands::WholeStreamCommand;
-use crate::errors::ShellError;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_macros::signature;
+use nu_protocol::{Signature, SyntaxShape};
 
-pub struct CD;
+pub struct Cd;
 
-impl WholeStreamCommand for CD {
+impl WholeStreamCommand for Cd {
     fn name(&self) -> &str {
         "cd"
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("cd").optional("directory", SyntaxShape::Path)
+        signature! {
+            def cd {
+                "the directory to change to"
+                directory(optional Path) - "the directory to change to"
+            }
+        }
+        // Signature::build("cd").optional(
+        //     "directory",
+        //     SyntaxShape::Path,
+        //     "the directory to change to",
+        // )
     }
 
     fn usage(&self) -> &str {

crates/nu-cli/src/commands/classified/dynamic.rs

@@ -0,0 +1,7 @@
+use derive_new::new;
+use nu_parser::hir;
+
+#[derive(new, Debug, Eq, PartialEq)]
+pub(crate) struct Command {
+    pub(crate) args: hir::Call,
+}

crates/nu-cli/src/commands/classified/external.rs

@@ -0,0 +1,853 @@
+use crate::futures::ThreadedReceiver;
+use crate::prelude::*;
+use bytes::{BufMut, Bytes, BytesMut};
+use futures::executor::block_on_stream;
+use futures::stream::StreamExt;
+use futures_codec::FramedRead;
+use log::trace;
+use nu_errors::ShellError;
+use nu_parser::commands::classified::external::ExternalArg;
+use nu_parser::ExternalCommand;
+use nu_protocol::{ColumnPath, Primitive, ShellTypeName, UntaggedValue, Value};
+use nu_source::{Tag, Tagged};
+use nu_value_ext::as_column_path;
+use std::io::Write;
+use std::ops::Deref;
+use std::process::{Command, Stdio};
+use std::sync::mpsc;
+
+pub enum StringOrBinary {
+    String(String),
+    Binary(Vec<u8>),
+}
+pub struct MaybeTextCodec;
+
+impl futures_codec::Encoder for MaybeTextCodec {
+    type Item = StringOrBinary;
+    type Error = std::io::Error;
+
+    fn encode(&mut self, item: Self::Item, dst: &mut BytesMut) -> Result<(), Self::Error> {
+        match item {
+            StringOrBinary::String(s) => {
+                dst.reserve(s.len());
+                dst.put(s.as_bytes());
+                Ok(())
+            }
+            StringOrBinary::Binary(b) => {
+                dst.reserve(b.len());
+                dst.put(Bytes::from(b));
+                Ok(())
+            }
+        }
+    }
+}
+
+impl futures_codec::Decoder for MaybeTextCodec {
+    type Item = StringOrBinary;
+    type Error = std::io::Error;
+
+    fn decode(&mut self, src: &mut BytesMut) -> Result<Option<Self::Item>, Self::Error> {
+        let v: Vec<u8> = src.to_vec();
+        match String::from_utf8(v) {
+            Ok(s) => {
+                src.clear();
+                if s.is_empty() {
+                    Ok(None)
+                } else {
+                    Ok(Some(StringOrBinary::String(s)))
+                }
+            }
+            Err(err) => {
+                // Note: the longest UTF-8 character per Unicode spec is currently 6 bytes. If we fail somewhere earlier than the last 6 bytes,
+                // we know that we're failing to understand the string encoding and not just seeing a partial character. When this happens, let's
+                // fall back to assuming it's a binary buffer.
+                if src.is_empty() {
+                    Ok(None)
+                } else if src.len() > 6 && (src.len() - err.utf8_error().valid_up_to() > 6) {
+                    // Fall back to assuming binary
+                    let buf = src.to_vec();
+                    src.clear();
+                    Ok(Some(StringOrBinary::Binary(buf)))
+                } else {
+                    // Looks like a utf-8 string, so let's assume that
+                    let buf = src.split_to(err.utf8_error().valid_up_to() + 1);
+                    String::from_utf8(buf.to_vec())
+                        .map(|x| Some(StringOrBinary::String(x)))
+                        .map_err(|e| std::io::Error::new(std::io::ErrorKind::InvalidData, e))
+                }
+            }
+        }
+    }
+}
+
+pub fn nu_value_to_string(command: &ExternalCommand, from: &Value) -> Result<String, ShellError> {
+    match &from.value {
+        UntaggedValue::Primitive(Primitive::Int(i)) => Ok(i.to_string()),
+        UntaggedValue::Primitive(Primitive::String(s))
+        | UntaggedValue::Primitive(Primitive::Line(s)) => Ok(s.clone()),
+        UntaggedValue::Primitive(Primitive::Path(p)) => Ok(p.to_string_lossy().to_string()),
+        unsupported => Err(ShellError::labeled_error(
+            format!("needs string data (given: {})", unsupported.type_name()),
+            "expected a string",
+            &command.name_tag,
+        )),
+    }
+}
+
+pub(crate) async fn run_external_command(
+    command: ExternalCommand,
+    context: &mut Context,
+    input: Option<InputStream>,
+    is_last: bool,
+) -> Result<Option<InputStream>, ShellError> {
+    trace!(target: "nu::run::external", "-> {}", command.name);
+
+    if !did_find_command(&command.name).await {
+        return Err(ShellError::labeled_error(
+            "Command not found",
+            "command not found",
+            &command.name_tag,
+        ));
+    }
+
+    if command.has_it_argument() || command.has_nu_argument() {
+        run_with_iterator_arg(command, context, input, is_last)
+    } else {
+        run_with_stdin(command, context, input, is_last)
+    }
+}
+
+fn prepare_column_path_for_fetching_it_variable(
+    argument: &ExternalArg,
+) -> Result<Tagged<ColumnPath>, ShellError> {
+    // We have "$it.[contents of interest]"
+    // and start slicing from "$it.[member+]"
+    //                             ^ here.
+    let key = nu_source::Text::from(argument.deref()).slice(4..argument.len());
+
+    to_column_path(&key, &argument.tag)
+}
+
+fn prepare_column_path_for_fetching_nu_variable(
+    argument: &ExternalArg,
+) -> Result<Tagged<ColumnPath>, ShellError> {
+    // We have "$nu.[contents of interest]"
+    // and start slicing from "$nu.[member+]"
+    //                             ^ here.
+    let key = nu_source::Text::from(argument.deref()).slice(4..argument.len());
+
+    to_column_path(&key, &argument.tag)
+}
+
+fn to_column_path(
+    path_members: &str,
+    tag: impl Into<Tag>,
+) -> Result<Tagged<ColumnPath>, ShellError> {
+    let tag = tag.into();
+
+    as_column_path(
+        &UntaggedValue::Table(
+            path_members
+                .split('.')
+                .map(|x| {
+                    let member = match x.parse::<u64>() {
+                        Ok(v) => UntaggedValue::int(v),
+                        Err(_) => UntaggedValue::string(x),
+                    };
+
+                    member.into_value(&tag)
+                })
+                .collect(),
+        )
+        .into_value(&tag),
+    )
+}
+
+fn run_with_iterator_arg(
+    command: ExternalCommand,
+    context: &mut Context,
+    input: Option<InputStream>,
+    is_last: bool,
+) -> Result<Option<InputStream>, ShellError> {
+    let path = context.shell_manager.path();
+
+    let mut inputs: InputStream = if let Some(input) = input {
+        trace_stream!(target: "nu::trace_stream::external::it", "input" = input)
+    } else {
+        InputStream::empty()
+    };
+
+    let stream = async_stream! {
+        while let Some(value) = inputs.next().await {
+            let name = command.name.clone();
+            let name_tag = command.name_tag.clone();
+            let home_dir = dirs::home_dir();
+            let path = &path;
+            let args = command.args.clone();
+
+            let it_replacement = {
+                if command.has_it_argument() {
+                    let empty_arg = ExternalArg {
+                        arg: "".to_string(),
+                        tag: name_tag.clone()
+                    };
+
+                    let key = args.iter()
+                        .find(|arg| arg.looks_like_it())
+                        .unwrap_or_else(|| &empty_arg);
+
+                    if args.iter().all(|arg| !arg.is_it()) {
+                        let key = match prepare_column_path_for_fetching_it_variable(&key) {
+                            Ok(keypath) => keypath,
+                            Err(reason) => {
+                                yield Ok(Value {
+                                    value: UntaggedValue::Error(reason),
+                                    tag: name_tag
+                                });
+                                return;
+                            }
+                        };
+
+                        match crate::commands::get::get_column_path(&key, &value) {
+                            Ok(field) => {
+                                match nu_value_to_string(&command, &field) {
+                                    Ok(val) => Some(val),
+                                    Err(reason) => {
+                                        yield Ok(Value {
+                                            value: UntaggedValue::Error(reason),
+                                            tag: name_tag
+                                        });
+                                        return;
+                                    },
+                                }
+                            },
+                            Err(reason) => {
+                                yield Ok(Value {
+                                    value: UntaggedValue::Error(reason),
+                                    tag: name_tag
+                                });
+                                return;
+                            }
+                        }
+                    } else {
+                        match nu_value_to_string(&command, &value) {
+                            Ok(val) => Some(val),
+                            Err(reason) => {
+                                yield Ok(Value {
+                                    value: UntaggedValue::Error(reason),
+                                    tag: name_tag
+                                });
+                                return;
+                            },
+                        }
+                    }
+                } else {
+                    None
+                }
+            };
+
+            let nu_replacement = {
+                if command.has_nu_argument() {
+                    let empty_arg = ExternalArg {
+                        arg: "".to_string(),
+                        tag: name_tag.clone()
+                    };
+
+                    let key = args.iter()
+                        .find(|arg| arg.looks_like_nu())
+                        .unwrap_or_else(|| &empty_arg);
+
+                    let nu_var = match crate::evaluate::variables::nu(&name_tag) {
+                        Ok(variables) => variables,
+                        Err(reason) => {
+                            yield Ok(Value {
+                                value: UntaggedValue::Error(reason),
+                                tag: name_tag
+                            });
+                            return;
+                        }
+                    };
+
+                    if args.iter().all(|arg| !arg.is_nu()) {
+                        let key = match prepare_column_path_for_fetching_nu_variable(&key) {
+                            Ok(keypath) => keypath,
+                            Err(reason) => {
+                                yield Ok(Value {
+                                    value: UntaggedValue::Error(reason),
+                                    tag: name_tag
+                                });
+                                return;
+                            }
+                        };
+
+                        match crate::commands::get::get_column_path(&key, &nu_var) {
+                            Ok(field) => {
+                                match nu_value_to_string(&command, &field) {
+                                    Ok(val) => Some(val),
+                                    Err(reason) => {
+                                        yield Ok(Value {
+                                            value: UntaggedValue::Error(reason),
+                                            tag: name_tag
+                                        });
+                                        return;
+                                    },
+                                }
+                            },
+                            Err(reason) => {
+                                yield Ok(Value {
+                                    value: UntaggedValue::Error(reason),
+                                    tag: name_tag
+                                });
+                                return;
+                            }
+                        }
+                    } else {
+                        match nu_value_to_string(&command, &nu_var) {
+                            Ok(val) => Some(val),
+                            Err(reason) => {
+                                yield Ok(Value {
+                                    value: UntaggedValue::Error(reason),
+                                    tag: name_tag
+                                });
+                                return;
+                            },
+                        }
+                    }
+                } else {
+                    None
+                }
+            };
+
+            let process_args = args.iter().filter_map(|arg| {
+                if arg.chars().all(|c| c.is_whitespace()) {
+                    None
+                } else {
+                    let arg = if arg.looks_like_it() {
+                        if let Some(mut value) = it_replacement.to_owned() {
+                            let mut value = expand_tilde(&value, || home_dir.as_ref()).as_ref().to_string();
+                            #[cfg(not(windows))]
+                            {
+                                value = {
+                                    if argument_contains_whitespace(&value) && !argument_is_quoted(&value) {
+                                        add_quotes(&value)
+                                    } else {
+                                        value
+                                    }
+                                };
+                            }
+                            Some(value)
+                        } else {
+                            None
+                        }
+                    } else if arg.looks_like_nu() {
+                        if let Some(mut value) = nu_replacement.to_owned() {
+                            #[cfg(not(windows))]
+                            {
+                                value = {
+                                    if argument_contains_whitespace(&value) && !argument_is_quoted(&value) {
+                                        add_quotes(&value)
+                                    } else {
+                                        value
+                                    }
+                                };
+                            }
+                            Some(value)
+                        } else {
+                            None
+                        }
+                    } else {
+                        Some(arg.to_string())
+                    };
+
+                    arg
+                }
+            }).collect::<Vec<String>>();
+
+            match spawn(&command, &path, &process_args[..], None, is_last) {
+                Ok(res) => {
+                    if let Some(mut res) = res {
+                        while let Some(item) = res.next().await {
+                            yield Ok(item)
+                        }
+                    }
+                }
+                Err(reason) => {
+                    yield Ok(Value {
+                        value: UntaggedValue::Error(reason),
+                        tag: name_tag
+                    });
+                    return;
+                }
+            }
+        }
+    };
+
+    Ok(Some(stream.to_input_stream()))
+}
+
+fn run_with_stdin(
+    command: ExternalCommand,
+    context: &mut Context,
+    input: Option<InputStream>,
+    is_last: bool,
+) -> Result<Option<InputStream>, ShellError> {
+    let path = context.shell_manager.path();
+
+    let input = input
+        .map(|input| trace_stream!(target: "nu::trace_stream::external::stdin", "input" = input));
+
+    let process_args = command
+        .args
+        .iter()
+        .map(|arg| {
+            let arg = expand_tilde(arg.deref(), dirs::home_dir);
+
+            #[cfg(not(windows))]
+            {
+                if argument_contains_whitespace(&arg) && argument_is_quoted(&arg) {
+                    if let Some(unquoted) = remove_quotes(&arg) {
+                        format!(r#""{}""#, unquoted)
+                    } else {
+                        arg.as_ref().to_string()
+                    }
+                } else {
+                    arg.as_ref().to_string()
+                }
+            }
+            #[cfg(windows)]
+            {
+                if let Some(unquoted) = remove_quotes(&arg) {
+                    unquoted.to_string()
+                } else {
+                    arg.as_ref().to_string()
+                }
+            }
+        })
+        .collect::<Vec<String>>();
+
+    spawn(&command, &path, &process_args[..], input, is_last)
+}
+
+fn spawn(
+    command: &ExternalCommand,
+    path: &str,
+    args: &[String],
+    input: Option<InputStream>,
+    is_last: bool,
+) -> Result<Option<InputStream>, ShellError> {
+    let command = command.clone();
+
+    let mut process = {
+        #[cfg(windows)]
+        {
+            let mut process = Command::new("cmd");
+            process.arg("/c");
+            process.arg(&command.name);
+            for arg in args {
+                process.arg(&arg);
+            }
+            process
+        }
+
+        #[cfg(not(windows))]
+        {
+            let cmd_with_args = vec![command.name.clone(), args.join(" ")].join(" ");
+            let mut process = Command::new("sh");
+            process.arg("-c").arg(cmd_with_args);
+            process
+        }
+    };
+
+    process.current_dir(path);
+    trace!(target: "nu::run::external", "cwd = {:?}", &path);
+
+    // We want stdout regardless of what
+    // we are doing ($it case or pipe stdin)
+    if !is_last {
+        process.stdout(Stdio::piped());
+        trace!(target: "nu::run::external", "set up stdout pipe");
+    }
+
+    // open since we have some contents for stdin
+    if input.is_some() {
+        process.stdin(Stdio::piped());
+        trace!(target: "nu::run::external", "set up stdin pipe");
+    }
+
+    trace!(target: "nu::run::external", "built command {:?}", process);
+
+    // TODO Switch to async_std::process once it's stabilized
+    if let Ok(mut child) = process.spawn() {
+        let (tx, rx) = mpsc::sync_channel(0);
+
+        let mut stdin = child.stdin.take();
+
+        let stdin_write_tx = tx.clone();
+        let stdout_read_tx = tx;
+        let stdin_name_tag = command.name_tag.clone();
+        let stdout_name_tag = command.name_tag;
+
+        std::thread::spawn(move || {
+            if let Some(input) = input {
+                let mut stdin_write = stdin
+                    .take()
+                    .expect("Internal error: could not get stdin pipe for external command");
+
+                for value in block_on_stream(input) {
+                    match &value.value {
+                        UntaggedValue::Primitive(Primitive::Nothing) => continue,
+                        UntaggedValue::Primitive(Primitive::String(s))
+                        | UntaggedValue::Primitive(Primitive::Line(s)) => {
+                            if let Err(e) = stdin_write.write(s.as_bytes()) {
+                                let message = format!("Unable to write to stdin (error = {})", e);
+
+                                let _ = stdin_write_tx.send(Ok(Value {
+                                    value: UntaggedValue::Error(ShellError::labeled_error(
+                                        message,
+                                        "application may have closed before completing pipeline",
+                                        &stdin_name_tag,
+                                    )),
+                                    tag: stdin_name_tag,
+                                }));
+                                return Err(());
+                            }
+                        }
+                        UntaggedValue::Primitive(Primitive::Binary(b)) => {
+                            if let Err(e) = stdin_write.write(b) {
+                                let message = format!("Unable to write to stdin (error = {})", e);
+
+                                let _ = stdin_write_tx.send(Ok(Value {
+                                    value: UntaggedValue::Error(ShellError::labeled_error(
+                                        message,
+                                        "application may have closed before completing pipeline",
+                                        &stdin_name_tag,
+                                    )),
+                                    tag: stdin_name_tag,
+                                }));
+                                return Err(());
+                            }
+                        }
+                        unsupported => {
+                            let _ = stdin_write_tx.send(Ok(Value {
+                                value: UntaggedValue::Error(ShellError::labeled_error(
+                                    format!(
+                                        "Received unexpected type from pipeline ({})",
+                                        unsupported.type_name()
+                                    ),
+                                    "expected a string",
+                                    stdin_name_tag.clone(),
+                                )),
+                                tag: stdin_name_tag,
+                            }));
+                            return Err(());
+                        }
+                    };
+                }
+            }
+
+            Ok(())
+        });
+
+        std::thread::spawn(move || {
+            if !is_last {
+                let stdout = if let Some(stdout) = child.stdout.take() {
+                    stdout
+                } else {
+                    let _ = stdout_read_tx.send(Ok(Value {
+                        value: UntaggedValue::Error(ShellError::labeled_error(
+                            "Can't redirect the stdout for external command",
+                            "can't redirect stdout",
+                            &stdout_name_tag,
+                        )),
+                        tag: stdout_name_tag,
+                    }));
+                    return Err(());
+                };
+
+                let file = futures::io::AllowStdIo::new(stdout);
+                let stream = FramedRead::new(file, MaybeTextCodec);
+
+                for line in block_on_stream(stream) {
+                    match line {
+                        Ok(line) => match line {
+                            StringOrBinary::String(s) => {
+                                let result = stdout_read_tx.send(Ok(Value {
+                                    value: UntaggedValue::Primitive(Primitive::String(s.clone())),
+                                    tag: stdout_name_tag.clone(),
+                                }));
+
+                                if result.is_err() {
+                                    break;
+                                }
+                            }
+                            StringOrBinary::Binary(b) => {
+                                let result = stdout_read_tx.send(Ok(Value {
+                                    value: UntaggedValue::Primitive(Primitive::Binary(
+                                        b.into_iter().collect(),
+                                    )),
+                                    tag: stdout_name_tag.clone(),
+                                }));
+
+                                if result.is_err() {
+                                    break;
+                                }
+                            }
+                        },
+                        Err(_) => {
+                            let _ = stdout_read_tx.send(Ok(Value {
+                                value: UntaggedValue::Error(ShellError::labeled_error(
+                                    "Unable to read from stdout.",
+                                    "unable to read from stdout",
+                                    &stdout_name_tag,
+                                )),
+                                tag: stdout_name_tag.clone(),
+                            }));
+                            break;
+                        }
+                    }
+                }
+            }
+
+            // We can give an error when we see a non-zero exit code, but this is different
+            // than what other shells will do.
+            if child.wait().is_err() {
+                let cfg = crate::data::config::config(Tag::unknown());
+                if let Ok(cfg) = cfg {
+                    if cfg.contains_key("nonzero_exit_errors") {
+                        let _ = stdout_read_tx.send(Ok(Value {
+                            value: UntaggedValue::Error(ShellError::labeled_error(
+                                "External command failed",
+                                "command failed",
+                                &stdout_name_tag,
+                            )),
+                            tag: stdout_name_tag,
+                        }));
+                    }
+                }
+            }
+
+            Ok(())
+        });
+
+        let stream = ThreadedReceiver::new(rx);
+        Ok(Some(stream.to_input_stream()))
+    } else {
+        Err(ShellError::labeled_error(
+            "Failed to spawn process",
+            "failed to spawn",
+            &command.name_tag,
+        ))
+    }
+}
+
+async fn did_find_command(name: &str) -> bool {
+    #[cfg(not(windows))]
+    {
+        ichwh::which(name).await.unwrap_or(None).is_some()
+    }
+
+    #[cfg(windows)]
+    {
+        if ichwh::which(name).await.unwrap_or(None).is_some() {
+            true
+        } else {
+            let cmd_builtins = [
+                "call", "cls", "color", "date", "dir", "echo", "find", "hostname", "pause",
+                "start", "time", "title", "ver", "copy", "mkdir", "rename", "rd", "rmdir", "type",
+            ];
+
+            cmd_builtins.contains(&name)
+        }
+    }
+}
+
+fn expand_tilde<SI: ?Sized, P, HD>(input: &SI, home_dir: HD) -> std::borrow::Cow<str>
+where
+    SI: AsRef<str>,
+    P: AsRef<std::path::Path>,
+    HD: FnOnce() -> Option<P>,
+{
+    shellexpand::tilde_with_context(input, home_dir)
+}
+
+#[allow(unused)]
+pub fn argument_contains_whitespace(argument: &str) -> bool {
+    argument.chars().any(|c| c.is_whitespace())
+}
+
+fn argument_is_quoted(argument: &str) -> bool {
+    if argument.len() < 2 {
+        return false;
+    }
+
+    (argument.starts_with('"') && argument.ends_with('"'))
+        || (argument.starts_with('\'') && argument.ends_with('\''))
+}
+
+#[allow(unused)]
+fn add_quotes(argument: &str) -> String {
+    format!("\"{}\"", argument)
+}
+
+fn remove_quotes(argument: &str) -> Option<&str> {
+    if !argument_is_quoted(argument) {
+        return None;
+    }
+
+    let size = argument.len();
+
+    Some(&argument[1..size - 1])
+}
+
+#[allow(unused)]
+fn shell_os_paths() -> Vec<std::path::PathBuf> {
+    let mut original_paths = vec![];
+
+    if let Some(paths) = std::env::var_os("PATH") {
+        original_paths = std::env::split_paths(&paths).collect::<Vec<_>>();
+    }
+
+    original_paths
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{
+        add_quotes, argument_contains_whitespace, argument_is_quoted, expand_tilde, remove_quotes,
+        run_external_command, Context,
+    };
+    use futures::executor::block_on;
+    use nu_errors::ShellError;
+    use nu_test_support::commands::ExternalBuilder;
+
+    // async fn read(mut stream: OutputStream) -> Option<Value> {
+    //     match stream.try_next().await {
+    //         Ok(val) => {
+    //             if let Some(val) = val {
+    //                 val.raw_value()
+    //             } else {
+    //                 None
+    //             }
+    //         }
+    //         Err(_) => None,
+    //     }
+    // }
+
+    async fn non_existent_run() -> Result<(), ShellError> {
+        let cmd = ExternalBuilder::for_name("i_dont_exist.exe").build();
+
+        let mut ctx = Context::basic().expect("There was a problem creating a basic context.");
+
+        assert!(run_external_command(cmd, &mut ctx, None, false)
+            .await
+            .is_err());
+
+        Ok(())
+    }
+
+    // async fn failure_run() -> Result<(), ShellError> {
+    //     let cmd = ExternalBuilder::for_name("fail").build();
+
+    //     let mut ctx = Context::basic().expect("There was a problem creating a basic context.");
+    //     let stream = run_external_command(cmd, &mut ctx, None, false)
+    //         .await?
+    //         .expect("There was a problem running the external command.");
+
+    //     match read(stream.into()).await {
+    //         Some(Value {
+    //             value: UntaggedValue::Error(_),
+    //             ..
+    //         }) => {}
+    //         None | _ => panic!("Command didn't fail."),
+    //     }
+
+    //     Ok(())
+    // }
+
+    // #[test]
+    // fn identifies_command_failed() -> Result<(), ShellError> {
+    //     block_on(failure_run())
+    // }
+
+    #[test]
+    fn identifies_command_not_found() -> Result<(), ShellError> {
+        block_on(non_existent_run())
+    }
+
+    #[test]
+    fn checks_contains_whitespace_from_argument_to_be_passed_in() {
+        assert_eq!(argument_contains_whitespace("andrés"), false);
+        assert_eq!(argument_contains_whitespace("and rés"), true);
+        assert_eq!(argument_contains_whitespace(r#"and\ rés"#), true);
+    }
+
+    #[test]
+    fn checks_quotes_from_argument_to_be_passed_in() {
+        assert_eq!(argument_is_quoted(""), false);
+
+        assert_eq!(argument_is_quoted("'"), false);
+        assert_eq!(argument_is_quoted("'a"), false);
+        assert_eq!(argument_is_quoted("a"), false);
+        assert_eq!(argument_is_quoted("a'"), false);
+        assert_eq!(argument_is_quoted("''"), true);
+
+        assert_eq!(argument_is_quoted(r#"""#), false);
+        assert_eq!(argument_is_quoted(r#""a"#), false);
+        assert_eq!(argument_is_quoted(r#"a"#), false);
+        assert_eq!(argument_is_quoted(r#"a""#), false);
+        assert_eq!(argument_is_quoted(r#""""#), true);
+
+        assert_eq!(argument_is_quoted("'andrés"), false);
+        assert_eq!(argument_is_quoted("andrés'"), false);
+        assert_eq!(argument_is_quoted(r#""andrés"#), false);
+        assert_eq!(argument_is_quoted(r#"andrés""#), false);
+        assert_eq!(argument_is_quoted("'andrés'"), true);
+        assert_eq!(argument_is_quoted(r#""andrés""#), true);
+    }
+
+    #[test]
+    fn adds_quotes_to_argument_to_be_passed_in() {
+        assert_eq!(add_quotes("andrés"), "\"andrés\"");
+        //assert_eq!(add_quotes("\"andrés\""), "\"andrés\"");
+    }
+
+    #[test]
+    fn strips_quotes_from_argument_to_be_passed_in() {
+        assert_eq!(remove_quotes(""), None);
+
+        assert_eq!(remove_quotes("'"), None);
+        assert_eq!(remove_quotes("'a"), None);
+        assert_eq!(remove_quotes("a"), None);
+        assert_eq!(remove_quotes("a'"), None);
+        assert_eq!(remove_quotes("''"), Some(""));
+
+        assert_eq!(remove_quotes(r#"""#), None);
+        assert_eq!(remove_quotes(r#""a"#), None);
+        assert_eq!(remove_quotes(r#"a"#), None);
+        assert_eq!(remove_quotes(r#"a""#), None);
+        assert_eq!(remove_quotes(r#""""#), Some(""));
+
+        assert_eq!(remove_quotes("'andrés"), None);
+        assert_eq!(remove_quotes("andrés'"), None);
+        assert_eq!(remove_quotes(r#""andrés"#), None);
+        assert_eq!(remove_quotes(r#"andrés""#), None);
+        assert_eq!(remove_quotes("'andrés'"), Some("andrés"));
+        assert_eq!(remove_quotes(r#""andrés""#), Some("andrés"));
+    }
+
+    #[test]
+    fn expands_tilde_if_starts_with_tilde_character() {
+        assert_eq!(
+            expand_tilde("~", || Some(std::path::Path::new("the_path_to_nu_light"))),
+            "the_path_to_nu_light"
+        );
+    }
+
+    #[test]
+    fn does_not_expand_tilde_if_tilde_is_not_first_character() {
+        assert_eq!(
+            expand_tilde("1~1", || Some(std::path::Path::new("the_path_to_nu_light"))),
+            "1~1"
+        );
+    }
+}

crates/nu-cli/src/commands/classified/internal.rs

@@ -0,0 +1,179 @@
+use crate::commands::UnevaluatedCallInfo;
+use crate::prelude::*;
+use log::{log_enabled, trace};
+use nu_errors::ShellError;
+use nu_parser::InternalCommand;
+use nu_protocol::{CommandAction, Primitive, ReturnSuccess, UntaggedValue, Value};
+
+pub(crate) fn run_internal_command(
+    command: InternalCommand,
+    context: &mut Context,
+    input: Option<InputStream>,
+    source: Text,
+) -> Result<Option<InputStream>, ShellError> {
+    if log_enabled!(log::Level::Trace) {
+        trace!(target: "nu::run::internal", "->");
+        trace!(target: "nu::run::internal", "{}", command.name);
+        trace!(target: "nu::run::internal", "{}", command.args.debug(&source));
+    }
+
+    let objects: InputStream = if let Some(input) = input {
+        trace_stream!(target: "nu::trace_stream::internal", "input" = input)
+    } else {
+        InputStream::empty()
+    };
+
+    let internal_command = context.expect_command(&command.name);
+
+    let result = {
+        context.run_command(
+            internal_command?,
+            command.name_tag.clone(),
+            command.args.clone(),
+            &source,
+            objects,
+        )
+    };
+
+    let result = trace_out_stream!(target: "nu::trace_stream::internal", "output" = result);
+    let mut result = result.values;
+    let mut context = context.clone();
+
+    let stream = async_stream! {
+        let mut soft_errs: Vec<ShellError> = vec![];
+        let mut yielded = false;
+
+        while let Some(item) = result.next().await {
+            match item {
+                Ok(ReturnSuccess::Action(action)) => match action {
+                    CommandAction::ChangePath(path) => {
+                        context.shell_manager.set_path(path);
+                    }
+                    CommandAction::Exit => std::process::exit(0), // TODO: save history.txt
+                    CommandAction::Error(err) => {
+                        context.error(err);
+                        break;
+                    }
+                    CommandAction::AutoConvert(tagged_contents, extension) => {
+                        let contents_tag = tagged_contents.tag.clone();
+                        let command_name = format!("from-{}", extension);
+                        let command = command.clone();
+                        if let Some(converter) = context.registry.get_command(&command_name) {
+                            let new_args = RawCommandArgs {
+                                host: context.host.clone(),
+                                ctrl_c: context.ctrl_c.clone(),
+                                shell_manager: context.shell_manager.clone(),
+                                call_info: UnevaluatedCallInfo {
+                                    args: nu_parser::hir::Call {
+                                        head: command.args.head,
+                                        positional: None,
+                                        named: None,
+                                        span: Span::unknown()
+                                    },
+                                    source: source.clone(),
+                                    name_tag: command.name_tag,
+                                }
+                            };
+                            let mut result = converter.run(new_args.with_input(vec![tagged_contents]), &context.registry);
+                            let result_vec: Vec<Result<ReturnSuccess, ShellError>> = result.drain_vec().await;
+                            for res in result_vec {
+                                match res {
+                                    Ok(ReturnSuccess::Value(Value { value: UntaggedValue::Table(list), ..})) => {
+                                        for l in list {
+                                            yield Ok(l);
+                                        }
+                                    }
+                                    Ok(ReturnSuccess::Value(Value { value, .. })) => {
+                                        yield Ok(value.into_value(contents_tag.clone()));
+                                    }
+                                    Err(e) => yield Err(e),
+                                    _ => {}
+                                }
+                            }
+                        } else {
+                            yield Ok(tagged_contents)
+                        }
+                    }
+                    CommandAction::EnterHelpShell(value) => {
+                        match value {
+                            Value {
+                                value: UntaggedValue::Primitive(Primitive::String(cmd)),
+                                tag,
+                            } => {
+                                context.shell_manager.insert_at_current(Box::new(
+                                    HelpShell::for_command(
+                                        UntaggedValue::string(cmd).into_value(tag),
+                                        &context.registry(),
+                                    )?,
+                                ));
+                            }
+                            _ => {
+                                context.shell_manager.insert_at_current(Box::new(
+                                    HelpShell::index(&context.registry())?,
+                                ));
+                            }
+                        }
+                    }
+                    CommandAction::EnterValueShell(value) => {
+                        context
+                            .shell_manager
+                            .insert_at_current(Box::new(ValueShell::new(value)));
+                    }
+                    CommandAction::EnterShell(location) => {
+                        context.shell_manager.insert_at_current(Box::new(
+                            FilesystemShell::with_location(location, context.registry().clone()),
+                        ));
+                    }
+                    CommandAction::PreviousShell => {
+                        context.shell_manager.prev();
+                    }
+                    CommandAction::NextShell => {
+                        context.shell_manager.next();
+                    }
+                    CommandAction::LeaveShell => {
+                        context.shell_manager.remove_at_current();
+                        if context.shell_manager.is_empty() {
+                            std::process::exit(0); // TODO: save history.txt
+                        }
+                    }
+                },
+
+                Ok(ReturnSuccess::Value(Value {
+                    value: UntaggedValue::Error(err),
+                    ..
+                })) => {
+                    context.error(err);
+                    break;
+                }
+
+                Ok(ReturnSuccess::Value(v)) => {
+                    yielded = true;
+                    yield Ok(v);
+                }
+
+                Ok(ReturnSuccess::DebugValue(v)) => {
+                    yielded = true;
+
+                    let doc = PrettyDebug::pretty_doc(&v);
+                    let mut buffer = termcolor::Buffer::ansi();
+
+                    let _ = doc.render_raw(
+                        context.with_host(|host| host.width() - 5),
+                        &mut nu_source::TermColored::new(&mut buffer),
+                    );
+
+                    let value = String::from_utf8_lossy(buffer.as_slice());
+
+                    yield Ok(UntaggedValue::string(value).into_untagged_value())
+                }
+
+                Err(err) => {
+                    context.error(err);
+                    break;
+                }
+            }
+        }
+    };
+
+    Ok(Some(stream.to_input_stream()))
+}

crates/nu-cli/src/commands/classified/mod.rs

@@ -0,0 +1,7 @@
+mod dynamic;
+pub(crate) mod external;
+pub(crate) mod internal;
+pub(crate) mod pipeline;
+
+#[allow(unused_imports)]
+pub(crate) use dynamic::Command as DynamicCommand;

crates/nu-cli/src/commands/classified/pipeline.rs

@@ -0,0 +1,50 @@
+use crate::commands::classified::external::run_external_command;
+use crate::commands::classified::internal::run_internal_command;
+use crate::context::Context;
+use crate::stream::InputStream;
+use nu_errors::ShellError;
+use nu_parser::{ClassifiedCommand, ClassifiedPipeline};
+use nu_source::Text;
+
+pub(crate) async fn run_pipeline(
+    pipeline: ClassifiedPipeline,
+    ctx: &mut Context,
+    mut input: Option<InputStream>,
+    line: &str,
+) -> Result<Option<InputStream>, ShellError> {
+    let mut iter = pipeline.commands.list.into_iter().peekable();
+
+    loop {
+        let item: Option<ClassifiedCommand> = iter.next();
+        let next: Option<&ClassifiedCommand> = iter.peek();
+
+        input = match (item, next) {
+            (Some(ClassifiedCommand::Dynamic(_)), _) | (_, Some(ClassifiedCommand::Dynamic(_))) => {
+                return Err(ShellError::unimplemented("Dynamic commands"))
+            }
+
+            (Some(ClassifiedCommand::Expr(_)), _) | (_, Some(ClassifiedCommand::Expr(_))) => {
+                return Err(ShellError::unimplemented("Expression-only commands"))
+            }
+
+            (Some(ClassifiedCommand::Error(err)), _) => return Err(err.into()),
+            (_, Some(ClassifiedCommand::Error(err))) => return Err(err.clone().into()),
+
+            (Some(ClassifiedCommand::Internal(left)), _) => {
+                run_internal_command(left, ctx, input, Text::from(line))?
+            }
+
+            (Some(ClassifiedCommand::External(left)), None) => {
+                run_external_command(left, ctx, input, true).await?
+            }
+
+            (Some(ClassifiedCommand::External(left)), _) => {
+                run_external_command(left, ctx, input, false).await?
+            }
+
+            (None, _) => break,
+        };
+    }
+
+    Ok(input)
+}

crates/nu-cli/src/commands/clear.rs

@@ -0,0 +1,40 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::Signature;
+use std::process::Command;
+
+pub struct Clear;
+
+impl WholeStreamCommand for Clear {
+    fn name(&self) -> &str {
+        "clear"
+    }
+    fn signature(&self) -> Signature {
+        Signature::build("clear")
+    }
+    fn usage(&self) -> &str {
+        "clears the terminal"
+    }
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        clear(args, registry)
+    }
+}
+fn clear(_args: CommandArgs, _registry: &CommandRegistry) -> Result<OutputStream, ShellError> {
+    if cfg!(windows) {
+        Command::new("cmd")
+            .args(&["/C", "cls"])
+            .status()
+            .expect("failed to execute process");
+    } else if cfg!(unix) {
+        Command::new("/bin/sh")
+            .args(&["-c", "clear"])
+            .status()
+            .expect("failed to execute process");
+    }
+    Ok(OutputStream::empty())
+}

crates/nu-cli/src/commands/clip.rs

@@ -0,0 +1,106 @@
+#[cfg(feature = "clipboard")]
+pub mod clipboard {
+    use crate::commands::WholeStreamCommand;
+    use crate::context::CommandRegistry;
+    use crate::prelude::*;
+    use futures::stream::StreamExt;
+    use nu_errors::ShellError;
+    use nu_protocol::{ReturnValue, Signature, Value};
+
+    use clipboard::{ClipboardContext, ClipboardProvider};
+
+    pub struct Clip;
+
+    #[derive(Deserialize)]
+    pub struct ClipArgs {}
+
+    impl WholeStreamCommand for Clip {
+        fn name(&self) -> &str {
+            "clip"
+        }
+
+        fn signature(&self) -> Signature {
+            Signature::build("clip")
+        }
+
+        fn usage(&self) -> &str {
+            "Copy the contents of the pipeline to the copy/paste buffer"
+        }
+
+        fn run(
+            &self,
+            args: CommandArgs,
+            registry: &CommandRegistry,
+        ) -> Result<OutputStream, ShellError> {
+            args.process(registry, clip)?.run()
+        }
+    }
+
+    pub fn clip(
+        ClipArgs {}: ClipArgs,
+        RunnableContext { input, name, .. }: RunnableContext,
+    ) -> Result<OutputStream, ShellError> {
+        let stream = async_stream! {
+            let values: Vec<Value> = input.values.collect().await;
+
+            let mut clip_stream = inner_clip(values, name).await;
+            while let Some(value) = clip_stream.next().await {
+                yield value;
+            }
+        };
+
+        let stream: BoxStream<'static, ReturnValue> = stream.boxed();
+
+        Ok(OutputStream::from(stream))
+    }
+
+    async fn inner_clip(input: Vec<Value>, name: Tag) -> OutputStream {
+        if let Ok(clip_context) = ClipboardProvider::new() {
+            let mut clip_context: ClipboardContext = clip_context;
+            let mut new_copy_data = String::new();
+
+            if !input.is_empty() {
+                let mut first = true;
+                for i in input.iter() {
+                    if !first {
+                        new_copy_data.push_str("\n");
+                    } else {
+                        first = false;
+                    }
+
+                    let string: String = match i.as_string() {
+                        Ok(string) => string.to_string(),
+                        Err(_) => {
+                            return OutputStream::one(Err(ShellError::labeled_error(
+                                "Given non-string data",
+                                "expected strings from pipeline",
+                                name,
+                            )))
+                        }
+                    };
+
+                    new_copy_data.push_str(&string);
+                }
+            }
+
+            match clip_context.set_contents(new_copy_data) {
+                Ok(_) => {}
+                Err(_) => {
+                    return OutputStream::one(Err(ShellError::labeled_error(
+                        "Could not set contents of clipboard",
+                        "could not set contents of clipboard",
+                        name,
+                    )));
+                }
+            }
+
+            OutputStream::empty()
+        } else {
+            OutputStream::one(Err(ShellError::labeled_error(
+                "Could not open clipboard",
+                "could not open clipboard",
+                name,
+            )))
+        }
+    }
+}

crates/nu-cli/src/commands/command.rs

@@ -1,15 +1,15 @@
-use crate::data::Value;
-use crate::errors::ShellError;
-use crate::evaluate::Scope;
-use crate::parser::hir;
-use crate::parser::{registry, ConfigDeserializer};
+use crate::commands::help::get_help;
+use crate::context::CommandRegistry;
+use crate::deserializer::ConfigDeserializer;
+use crate::evaluate::evaluate_args::evaluate_args;
 use crate::prelude::*;
 use derive_new::new;
 use getset::Getters;
+use nu_errors::ShellError;
+use nu_parser::hir;
+use nu_protocol::{CallInfo, EvaluatedArgs, ReturnValue, Scope, Signature, Value};
 use serde::{Deserialize, Serialize};
-use std::fmt;
 use std::ops::Deref;
-use std::path::PathBuf;
 use std::sync::atomic::AtomicBool;
 
 #[derive(Deserialize, Serialize, Debug, Clone)]
@@ -19,37 +19,39 @@ pub struct UnevaluatedCallInfo {
     pub name_tag: Tag,
 }
 
-impl ToDebug for UnevaluatedCallInfo {
-    fn fmt_debug(&self, f: &mut fmt::Formatter, source: &str) -> fmt::Result {
-        self.args.fmt_debug(f, source)
-    }
-}
-
 impl UnevaluatedCallInfo {
     pub fn evaluate(
         self,
-        registry: &registry::CommandRegistry,
+        registry: &CommandRegistry,
         scope: &Scope,
     ) -> Result<CallInfo, ShellError> {
-        let args = self.args.evaluate(registry, scope, &self.source)?;
+        let args = evaluate_args(&self.args, registry, scope, &self.source)?;
 
         Ok(CallInfo {
             args,
             name_tag: self.name_tag,
         })
     }
+
+    pub fn switch_present(&self, switch: &str) -> bool {
+        self.args.switch_preset(switch)
+    }
 }
 
-#[derive(Deserialize, Serialize, Debug, Clone)]
-pub struct CallInfo {
-    pub args: registry::EvaluatedArgs,
-    pub name_tag: Tag,
-}
-
-impl CallInfo {
-    pub fn process<'de, T: Deserialize<'de>>(
+pub trait CallInfoExt {
+    fn process<'de, T: Deserialize<'de>>(
         &self,
         shell_manager: &ShellManager,
+        ctrl_c: Arc<AtomicBool>,
+        callback: fn(T, &RunnablePerItemContext) -> Result<OutputStream, ShellError>,
+    ) -> Result<RunnablePerItemArgs<T>, ShellError>;
+}
+
+impl CallInfoExt for CallInfo {
+    fn process<'de, T: Deserialize<'de>>(
+        &self,
+        shell_manager: &ShellManager,
+        ctrl_c: Arc<AtomicBool>,
         callback: fn(T, &RunnablePerItemContext) -> Result<OutputStream, ShellError>,
     ) -> Result<RunnablePerItemArgs<T>, ShellError> {
         let mut deserializer = ConfigDeserializer::from_call_info(self.clone());
@@ -59,6 +61,7 @@ impl CallInfo {
             context: RunnablePerItemContext {
                 shell_manager: shell_manager.clone(),
                 name: self.name_tag.clone(),
+                ctrl_c,
             },
             callback,
         })
@@ -68,7 +71,7 @@ impl CallInfo {
 #[derive(Getters)]
 #[get = "pub(crate)"]
 pub struct CommandArgs {
-    pub host: Arc<Mutex<dyn Host>>,
+    pub host: Arc<parking_lot::Mutex<Box<dyn Host>>>,
     pub ctrl_c: Arc<AtomicBool>,
     pub shell_manager: ShellManager,
     pub call_info: UnevaluatedCallInfo,
@@ -78,14 +81,14 @@ pub struct CommandArgs {
 #[derive(Getters, Clone)]
 #[get = "pub(crate)"]
 pub struct RawCommandArgs {
-    pub host: Arc<Mutex<dyn Host>>,
+    pub host: Arc<parking_lot::Mutex<Box<dyn Host>>>,
     pub ctrl_c: Arc<AtomicBool>,
     pub shell_manager: ShellManager,
     pub call_info: UnevaluatedCallInfo,
 }
 
 impl RawCommandArgs {
-    pub fn with_input(self, input: Vec<Tagged<Value>>) -> CommandArgs {
+    pub fn with_input(self, input: impl Into<InputStream>) -> CommandArgs {
         CommandArgs {
             host: self.host,
             ctrl_c: self.ctrl_c,
@@ -96,16 +99,16 @@ impl RawCommandArgs {
     }
 }
 
-impl ToDebug for CommandArgs {
-    fn fmt_debug(&self, f: &mut fmt::Formatter, source: &str) -> fmt::Result {
-        self.call_info.fmt_debug(f, source)
+impl std::fmt::Debug for CommandArgs {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        self.call_info.fmt(f)
     }
 }
 
 impl CommandArgs {
     pub fn evaluate_once(
         self,
-        registry: &registry::CommandRegistry,
+        registry: &CommandRegistry,
     ) -> Result<EvaluatedWholeStreamCommandArgs, ShellError> {
         let host = self.host.clone();
         let ctrl_c = self.ctrl_c.clone();
@@ -122,13 +125,38 @@ impl CommandArgs {
         ))
     }
 
-    pub fn process<'de, T: Deserialize<'de>>(
+    pub fn evaluate_once_with_scope(
         self,
         registry: &CommandRegistry,
-        callback: fn(T, RunnableContext) -> Result<OutputStream, ShellError>,
-    ) -> Result<RunnableArgs<T>, ShellError> {
+        scope: &Scope,
+    ) -> Result<EvaluatedWholeStreamCommandArgs, ShellError> {
+        let host = self.host.clone();
+        let ctrl_c = self.ctrl_c.clone();
+        let shell_manager = self.shell_manager.clone();
+        let input = self.input;
+        let call_info = self.call_info.evaluate(registry, scope)?;
+
+        Ok(EvaluatedWholeStreamCommandArgs::new(
+            host,
+            ctrl_c,
+            shell_manager,
+            call_info,
+            input,
+        ))
+    }
+
+    pub fn source(&self) -> Text {
+        self.call_info.source.clone()
+    }
+
+    pub fn process<'de, T: Deserialize<'de>, O: ToOutputStream>(
+        self,
+        registry: &CommandRegistry,
+        callback: fn(T, RunnableContext) -> Result<O, ShellError>,
+    ) -> Result<RunnableArgs<T, O>, ShellError> {
         let shell_manager = self.shell_manager.clone();
         let host = self.host.clone();
+        let source = self.source();
         let ctrl_c = self.ctrl_c.clone();
         let args = self.evaluate_once(registry)?;
         let call_info = args.call_info.clone();
@@ -141,6 +169,7 @@ impl CommandArgs {
             context: RunnableContext {
                 input,
                 commands: registry.clone(),
+                source,
                 shell_manager,
                 name: name_tag,
                 host,
@@ -164,19 +193,21 @@ impl CommandArgs {
 
         let shell_manager = self.shell_manager.clone();
         let host = self.host.clone();
+        let source = self.source();
         let ctrl_c = self.ctrl_c.clone();
         let args = self.evaluate_once(registry)?;
         let call_info = args.call_info.clone();
 
         let (input, args) = args.split();
         let name_tag = args.call_info.name_tag;
-        let mut deserializer = ConfigDeserializer::from_call_info(call_info.clone());
+        let mut deserializer = ConfigDeserializer::from_call_info(call_info);
 
         Ok(RunnableRawArgs {
             args: T::deserialize(&mut deserializer)?,
             context: RunnableContext {
                 input,
                 commands: registry.clone(),
+                source,
                 shell_manager,
                 name: name_tag,
                 host,
@@ -191,18 +222,14 @@ impl CommandArgs {
 pub struct RunnablePerItemContext {
     pub shell_manager: ShellManager,
     pub name: Tag,
-}
-
-impl RunnablePerItemContext {
-    pub fn cwd(&self) -> PathBuf {
-        PathBuf::from(self.shell_manager.path())
-    }
+    pub ctrl_c: Arc<AtomicBool>,
 }
 
 pub struct RunnableContext {
     pub input: InputStream,
     pub shell_manager: ShellManager,
-    pub host: Arc<Mutex<dyn Host>>,
+    pub host: Arc<parking_lot::Mutex<Box<dyn Host>>>,
+    pub source: Text,
     pub ctrl_c: Arc<AtomicBool>,
     pub commands: CommandRegistry,
     pub name: Tag,
@@ -226,15 +253,15 @@ impl<T> RunnablePerItemArgs<T> {
     }
 }
 
-pub struct RunnableArgs<T> {
+pub struct RunnableArgs<T, O: ToOutputStream> {
     args: T,
     context: RunnableContext,
-    callback: fn(T, RunnableContext) -> Result<OutputStream, ShellError>,
+    callback: fn(T, RunnableContext) -> Result<O, ShellError>,
 }
 
-impl<T> RunnableArgs<T> {
+impl<T, O: ToOutputStream> RunnableArgs<T, O> {
     pub fn run(self) -> Result<OutputStream, ShellError> {
-        (self.callback)(self.args, self.context)
+        (self.callback)(self.args, self.context).map(|v| v.to_output_stream())
     }
 }
 
@@ -268,7 +295,7 @@ impl Deref for EvaluatedWholeStreamCommandArgs {
 
 impl EvaluatedWholeStreamCommandArgs {
     pub fn new(
-        host: Arc<Mutex<dyn Host>>,
+        host: Arc<parking_lot::Mutex<dyn Host>>,
         ctrl_c: Arc<AtomicBool>,
         shell_manager: ShellManager,
         call_info: CallInfo,
@@ -289,7 +316,7 @@ impl EvaluatedWholeStreamCommandArgs {
         self.args.call_info.name_tag.clone()
     }
 
-    pub fn parts(self) -> (InputStream, registry::EvaluatedArgs) {
+    pub fn parts(self) -> (InputStream, EvaluatedArgs) {
         let EvaluatedWholeStreamCommandArgs { args, input } = self;
 
         (input, args.call_info.args)
@@ -317,7 +344,7 @@ impl Deref for EvaluatedFilterCommandArgs {
 
 impl EvaluatedFilterCommandArgs {
     pub fn new(
-        host: Arc<Mutex<dyn Host>>,
+        host: Arc<parking_lot::Mutex<dyn Host>>,
         ctrl_c: Arc<AtomicBool>,
         shell_manager: ShellManager,
         call_info: CallInfo,
@@ -336,128 +363,31 @@ impl EvaluatedFilterCommandArgs {
 #[derive(Getters, new)]
 #[get = "pub(crate)"]
 pub struct EvaluatedCommandArgs {
-    pub host: Arc<Mutex<dyn Host>>,
+    pub host: Arc<parking_lot::Mutex<dyn Host>>,
     pub ctrl_c: Arc<AtomicBool>,
     pub shell_manager: ShellManager,
     pub call_info: CallInfo,
 }
 
 impl EvaluatedCommandArgs {
-    pub fn call_args(&self) -> &registry::EvaluatedArgs {
-        &self.call_info.args
-    }
-
-    pub fn nth(&self, pos: usize) -> Option<&Tagged<Value>> {
+    pub fn nth(&self, pos: usize) -> Option<&Value> {
         self.call_info.args.nth(pos)
     }
 
-    pub fn expect_nth(&self, pos: usize) -> Result<&Tagged<Value>, ShellError> {
-        self.call_info.args.expect_nth(pos)
-    }
-
-    pub fn len(&self) -> usize {
-        self.call_info.args.len()
-    }
-
-    pub fn get(&self, name: &str) -> Option<&Tagged<Value>> {
+    pub fn get(&self, name: &str) -> Option<&Value> {
         self.call_info.args.get(name)
     }
 
-    pub fn slice_from(&self, from: usize) -> Vec<Tagged<Value>> {
-        let positional = &self.call_info.args.positional;
-
-        match positional {
-            None => vec![],
-            Some(list) => list[from..].to_vec(),
-        }
-    }
-
     pub fn has(&self, name: &str) -> bool {
         self.call_info.args.has(name)
     }
 }
 
-#[derive(Debug, Serialize, Deserialize)]
-pub enum CommandAction {
-    ChangePath(String),
-    Exit,
-    EnterShell(String),
-    EnterValueShell(Tagged<Value>),
-    EnterHelpShell(Tagged<Value>),
-    PreviousShell,
-    NextShell,
-    LeaveShell,
-}
-
-impl ToDebug for CommandAction {
-    fn fmt_debug(&self, f: &mut fmt::Formatter, _source: &str) -> fmt::Result {
-        match self {
-            CommandAction::ChangePath(s) => write!(f, "action:change-path={}", s),
-            CommandAction::Exit => write!(f, "action:exit"),
-            CommandAction::EnterShell(s) => write!(f, "action:enter-shell={}", s),
-            CommandAction::EnterValueShell(t) => {
-                write!(f, "action:enter-value-shell={:?}", t.debug())
-            }
-            CommandAction::EnterHelpShell(t) => {
-                write!(f, "action:enter-help-shell={:?}", t.debug())
-            }
-            CommandAction::PreviousShell => write!(f, "action:previous-shell"),
-            CommandAction::NextShell => write!(f, "action:next-shell"),
-            CommandAction::LeaveShell => write!(f, "action:leave-shell"),
-        }
-    }
-}
-
-#[derive(Debug, Serialize, Deserialize)]
-pub enum ReturnSuccess {
-    Value(Tagged<Value>),
-    Action(CommandAction),
-}
-
-pub type ReturnValue = Result<ReturnSuccess, ShellError>;
-
-impl ToDebug for ReturnValue {
-    fn fmt_debug(&self, f: &mut fmt::Formatter, source: &str) -> fmt::Result {
-        match self {
-            Err(err) => write!(f, "{}", err.debug(source)),
-            Ok(ReturnSuccess::Value(v)) => write!(f, "{:?}", v.debug()),
-            Ok(ReturnSuccess::Action(a)) => write!(f, "{}", a.debug(source)),
-        }
-    }
-}
-
-impl From<Tagged<Value>> for ReturnValue {
-    fn from(input: Tagged<Value>) -> ReturnValue {
-        Ok(ReturnSuccess::Value(input))
-    }
-}
-
-impl ReturnSuccess {
-    pub fn change_cwd(path: String) -> ReturnValue {
-        Ok(ReturnSuccess::Action(CommandAction::ChangePath(path)))
-    }
-
-    pub fn value(input: impl Into<Tagged<Value>>) -> ReturnValue {
-        Ok(ReturnSuccess::Value(input.into()))
-    }
-
-    pub fn action(input: CommandAction) -> ReturnValue {
-        Ok(ReturnSuccess::Action(input))
-    }
-}
-
 pub trait WholeStreamCommand: Send + Sync {
     fn name(&self) -> &str;
 
     fn signature(&self) -> Signature {
-        Signature {
-            name: self.name().to_string(),
-            usage: self.usage().to_string(),
-            positional: vec![],
-            rest_positional: None,
-            named: indexmap::IndexMap::new(),
-            is_filter: true,
-        }
+        Signature::new(self.name()).desc(self.usage()).filter()
     }
 
     fn usage(&self) -> &str;
@@ -465,7 +395,7 @@ pub trait WholeStreamCommand: Send + Sync {
     fn run(
         &self,
         args: CommandArgs,
-        registry: &registry::CommandRegistry,
+        registry: &CommandRegistry,
     ) -> Result<OutputStream, ShellError>;
 
     fn is_binary(&self) -> bool {
@@ -477,14 +407,7 @@ pub trait PerItemCommand: Send + Sync {
     fn name(&self) -> &str;
 
     fn signature(&self) -> Signature {
-        Signature {
-            name: self.name().to_string(),
-            usage: self.usage().to_string(),
-            positional: vec![],
-            rest_positional: None,
-            named: indexmap::IndexMap::new(),
-            is_filter: true,
-        }
+        Signature::new(self.name()).desc(self.usage()).filter()
     }
 
     fn usage(&self) -> &str;
@@ -494,7 +417,7 @@ pub trait PerItemCommand: Send + Sync {
         call_info: &CallInfo,
         registry: &CommandRegistry,
         raw_args: &RawCommandArgs,
-        input: Tagged<Value>,
+        input: Value,
     ) -> Result<OutputStream, ShellError>;
 
     fn is_binary(&self) -> bool {
@@ -507,6 +430,29 @@ pub enum Command {
     PerItem(Arc<dyn PerItemCommand>),
 }
 
+impl PrettyDebugWithSource for Command {
+    fn pretty_debug(&self, source: &str) -> DebugDocBuilder {
+        match self {
+            Command::WholeStream(command) => b::typed(
+                "whole stream command",
+                b::description(command.name())
+                    + b::space()
+                    + b::equals()
+                    + b::space()
+                    + command.signature().pretty_debug(source),
+            ),
+            Command::PerItem(command) => b::typed(
+                "per item command",
+                b::description(command.name())
+                    + b::space()
+                    + b::equals()
+                    + b::space()
+                    + command.signature().pretty_debug(source),
+            ),
+        }
+    }
+}
+
 impl std::fmt::Debug for Command {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
@@ -538,19 +484,18 @@ impl Command {
         }
     }
 
-    pub fn run(
-        &self,
-        args: CommandArgs,
-        registry: &registry::CommandRegistry,
-        is_first_command: bool,
-    ) -> OutputStream {
-        match self {
-            Command::WholeStream(command) => match command.run(args, registry) {
-                Ok(stream) => stream,
-                Err(err) => OutputStream::one(Err(err)),
-            },
-            Command::PerItem(command) => {
-                self.run_helper(command.clone(), args, registry.clone(), is_first_command)
+    pub fn run(&self, args: CommandArgs, registry: &CommandRegistry) -> OutputStream {
+        if args.call_info.switch_present("help") {
+            get_help(self.name(), self.usage(), self.signature()).into()
+        } else {
+            match self {
+                Command::WholeStream(command) => match command.run(args, registry) {
+                    Ok(stream) => stream,
+                    Err(err) => OutputStream::one(Err(err)),
+                },
+                Command::PerItem(command) => {
+                    self.run_helper(command.clone(), args, registry.clone())
+                }
             }
         }
     }
@@ -560,7 +505,6 @@ impl Command {
         command: Arc<dyn PerItemCommand>,
         args: CommandArgs,
         registry: CommandRegistry,
-        is_first_command: bool,
     ) -> OutputStream {
         let raw_args = RawCommandArgs {
             host: args.host,
@@ -569,40 +513,28 @@ impl Command {
             call_info: args.call_info,
         };
 
-        if !is_first_command {
-            let out = args
-                .input
-                .values
-                .map(move |x| {
-                    let call_info = raw_args
-                        .clone()
-                        .call_info
-                        .evaluate(&registry, &Scope::it_value(x.clone()))
-                        .unwrap();
-                    match command.run(&call_info, &registry, &raw_args, x) {
+        let out = args
+            .input
+            .values
+            .map(move |x| {
+                let call_info = raw_args
+                    .clone()
+                    .call_info
+                    .evaluate(&registry, &Scope::it_value(x.clone()));
+
+                match call_info {
+                    Ok(call_info) => match command.run(&call_info, &registry, &raw_args, x) {
                         Ok(o) => o,
-                        Err(e) => VecDeque::from(vec![ReturnValue::Err(e)]).to_output_stream(),
-                    }
-                })
-                .flatten();
+                        Err(e) => {
+                            futures::stream::iter(vec![ReturnValue::Err(e)]).to_output_stream()
+                        }
+                    },
+                    Err(e) => futures::stream::iter(vec![ReturnValue::Err(e)]).to_output_stream(),
+                }
+            })
+            .flatten();
 
-            out.to_output_stream()
-        } else {
-            let nothing = Value::nothing().tagged(Tag::unknown());
-            let call_info = raw_args
-                .clone()
-                .call_info
-                .evaluate(&registry, &Scope::it_value(nothing.clone()))
-                .unwrap();
-
-            match command
-                .run(&call_info, &registry, &raw_args, nothing)
-                .into()
-            {
-                Ok(o) => o,
-                Err(e) => OutputStream::one(Err(e)),
-            }
-        }
+        out.to_output_stream()
     }
 
     pub fn is_binary(&self) -> bool {
@@ -630,7 +562,7 @@ impl WholeStreamCommand for FnFilterCommand {
     fn run(
         &self,
         args: CommandArgs,
-        registry: &registry::CommandRegistry,
+        registry: &CommandRegistry,
     ) -> Result<OutputStream, ShellError> {
         let CommandArgs {
             host,
@@ -640,9 +572,8 @@ impl WholeStreamCommand for FnFilterCommand {
             input,
         } = args;
 
-        let host: Arc<Mutex<dyn Host>> = host.clone();
-        let shell_manager = shell_manager.clone();
-        let registry: registry::CommandRegistry = registry.clone();
+        let host: Arc<parking_lot::Mutex<dyn Host>> = host.clone();
+        let registry: CommandRegistry = registry.clone();
         let func = self.func;
 
         let result = input.values.map(move |it| {
@@ -660,7 +591,7 @@ impl WholeStreamCommand for FnFilterCommand {
             );
 
             match func(args) {
-                Err(err) => return OutputStream::from(vec![Err(err)]).values,
+                Err(err) => OutputStream::from(vec![Err(err)]).values,
                 Ok(stream) => stream.values,
             }
         });

crates/nu-cli/src/commands/compact.rs

@@ -0,0 +1,61 @@
+use crate::commands::WholeStreamCommand;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use futures::stream::StreamExt;
+use nu_errors::ShellError;
+use nu_protocol::{Signature, SyntaxShape, UntaggedValue, Value};
+use nu_source::Tagged;
+
+pub struct Compact;
+
+#[derive(Deserialize)]
+pub struct CompactArgs {
+    rest: Vec<Tagged<String>>,
+}
+
+impl WholeStreamCommand for Compact {
+    fn name(&self) -> &str {
+        "compact"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("compact").rest(SyntaxShape::Any, "the columns to compact from the table")
+    }
+
+    fn usage(&self) -> &str {
+        "Creates a table with non-empty rows"
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, compact)?.run()
+    }
+}
+
+pub fn compact(
+    CompactArgs { rest: columns }: CompactArgs,
+    RunnableContext { input, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let objects = input.values.filter(move |item| {
+        let keep = if columns.is_empty() {
+            item.is_some()
+        } else {
+            match item {
+                Value {
+                    value: UntaggedValue::Row(ref r),
+                    ..
+                } => columns
+                    .iter()
+                    .all(|field| r.get_data(field).borrow().is_some()),
+                _ => false,
+            }
+        };
+
+        futures::future::ready(keep)
+    });
+
+    Ok(objects.from_input_stream())
+}

crates/nu-cli/src/commands/config.rs

@@ -0,0 +1,188 @@
+use crate::commands::WholeStreamCommand;
+use crate::context::CommandRegistry;
+use crate::data::config;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_source::Tagged;
+use std::path::PathBuf;
+
+pub struct Config;
+
+#[derive(Deserialize)]
+pub struct ConfigArgs {
+    load: Option<Tagged<PathBuf>>,
+    set: Option<(Tagged<String>, Value)>,
+    set_into: Option<Tagged<String>>,
+    get: Option<Tagged<String>>,
+    clear: Tagged<bool>,
+    remove: Option<Tagged<String>>,
+    path: Tagged<bool>,
+}
+
+impl WholeStreamCommand for Config {
+    fn name(&self) -> &str {
+        "config"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("config")
+            .named(
+                "load",
+                SyntaxShape::Path,
+                "load the config from the path give",
+                Some('l'),
+            )
+            .named(
+                "set",
+                SyntaxShape::Any,
+                "set a value in the config, eg) --set [key value]",
+                Some('s'),
+            )
+            .named(
+                "set_into",
+                SyntaxShape::Member,
+                "sets a variable from values in the pipeline",
+                Some('i'),
+            )
+            .named(
+                "get",
+                SyntaxShape::Any,
+                "get a value from the config",
+                Some('g'),
+            )
+            .named(
+                "remove",
+                SyntaxShape::Any,
+                "remove a value from the config",
+                Some('r'),
+            )
+            .switch("clear", "clear the config", Some('c'))
+            .switch("path", "return the path to the config file", Some('p'))
+    }
+
+    fn usage(&self) -> &str {
+        "Configuration management."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, config)?.run()
+    }
+}
+
+pub fn config(
+    ConfigArgs {
+        load,
+        set,
+        set_into,
+        get,
+        clear,
+        remove,
+        path,
+    }: ConfigArgs,
+    RunnableContext { name, input, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let name_span = name.clone();
+
+    let stream = async_stream! {
+        let configuration = if let Some(supplied) = load {
+            Some(supplied.item().clone())
+        } else {
+            None
+        };
+
+        let mut result = crate::data::config::read(name_span, &configuration)?;
+
+        if let Some(v) = get {
+            let key = v.to_string();
+            let value = result
+                .get(&key)
+                .ok_or_else(|| ShellError::labeled_error("Missing key in config", "key", v.tag()))?;
+
+            match value {
+                Value {
+                    value: UntaggedValue::Table(list),
+                    ..
+                } => {
+                    for l in list {
+                        let value = l.clone();
+                        yield ReturnSuccess::value(l.clone());
+                    }
+                }
+                x => yield ReturnSuccess::value(x.clone()),
+            }
+        }
+        else if let Some((key, value)) = set {
+            result.insert(key.to_string(), value.clone());
+
+            config::write(&result, &configuration)?;
+
+            yield ReturnSuccess::value(UntaggedValue::Row(result.into()).into_value(&value.tag));
+        }
+        else if let Some(v) = set_into {
+            let rows: Vec<Value> = input.values.collect().await;
+            let key = v.to_string();
+
+            if rows.len() == 0 {
+                yield Err(ShellError::labeled_error("No values given for set_into", "needs value(s) from pipeline", v.tag()));
+            } else if rows.len() == 1 {
+                // A single value
+                let value = &rows[0];
+
+                result.insert(key.to_string(), value.clone());
+
+                config::write(&result, &configuration)?;
+
+                yield ReturnSuccess::value(UntaggedValue::Row(result.into()).into_value(name));
+            } else {
+                // Take in the pipeline as a table
+                let value = UntaggedValue::Table(rows).into_value(name.clone());
+
+                result.insert(key.to_string(), value.clone());
+
+                config::write(&result, &configuration)?;
+
+                yield ReturnSuccess::value(UntaggedValue::Row(result.into()).into_value(name));
+            }
+        }
+        else if let Tagged { item: true, tag } = clear {
+            result.clear();
+
+            config::write(&result, &configuration)?;
+
+            yield ReturnSuccess::value(UntaggedValue::Row(result.into()).into_value(tag));
+
+            return;
+        }
+        else if let Tagged { item: true, tag } = path {
+            let path = config::default_path_for(&configuration)?;
+
+            yield ReturnSuccess::value(UntaggedValue::Primitive(Primitive::Path(path)).into_value(tag));
+        }
+        else if let Some(v) = remove {
+            let key = v.to_string();
+
+            if result.contains_key(&key) {
+                result.swap_remove(&key);
+                config::write(&result, &configuration)?
+            } else {
+                yield Err(ShellError::labeled_error(
+                    "Key does not exist in config",
+                    "key",
+                    v.tag(),
+                ));
+            }
+
+            yield ReturnSuccess::value(UntaggedValue::Row(result.into()).into_value(v.tag()));
+        }
+        else {
+            yield ReturnSuccess::value(UntaggedValue::Row(result.into()).into_value(name));
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/count.rs

@@ -1,9 +1,9 @@
 use crate::commands::WholeStreamCommand;
-use crate::data::Value;
-use crate::errors::ShellError;
-use crate::parser::CommandRegistry;
+use crate::context::CommandRegistry;
 use crate::prelude::*;
 use futures::stream::StreamExt;
+use nu_errors::ShellError;
+use nu_protocol::{ReturnSuccess, Signature, UntaggedValue, Value};
 
 pub struct Count;
 
@@ -37,9 +37,9 @@ pub fn count(
     RunnableContext { input, name, .. }: RunnableContext,
 ) -> Result<OutputStream, ShellError> {
     let stream = async_stream! {
-        let rows: Vec<Tagged<Value>> = input.values.collect().await;
+        let rows: Vec<Value> = input.values.collect().await;
 
-        yield ReturnSuccess::value(Value::int(rows.len()).tagged(name))
+        yield ReturnSuccess::value(UntaggedValue::int(rows.len()).into_value(name))
     };
 
     Ok(stream.to_output_stream())

crates/nu-cli/src/commands/cp.rs

@@ -1,8 +1,9 @@
 use crate::commands::command::RunnablePerItemContext;
-use crate::errors::ShellError;
-use crate::parser::hir::SyntaxShape;
-use crate::parser::registry::{CommandRegistry, Signature};
+use crate::context::CommandRegistry;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CallInfo, Signature, SyntaxShape, Value};
+use nu_source::Tagged;
 use std::path::PathBuf;
 
 pub struct Cpy;
@@ -21,10 +22,13 @@ impl PerItemCommand for Cpy {
 
     fn signature(&self) -> Signature {
         Signature::build("cp")
-            .required("src", SyntaxShape::Pattern)
-            .required("dst", SyntaxShape::Path)
-            .named("file", SyntaxShape::Any)
-            .switch("recursive")
+            .required("src", SyntaxShape::Pattern, "the place to copy from")
+            .required("dst", SyntaxShape::Path, "the place to copy to")
+            .switch(
+                "recursive",
+                "copy recursively through subdirectories",
+                Some('r'),
+            )
     }
 
     fn usage(&self) -> &str {
@@ -36,9 +40,11 @@ impl PerItemCommand for Cpy {
         call_info: &CallInfo,
         _registry: &CommandRegistry,
         raw_args: &RawCommandArgs,
-        _input: Tagged<Value>,
+        _input: Value,
     ) -> Result<OutputStream, ShellError> {
-        call_info.process(&raw_args.shell_manager, cp)?.run()
+        call_info
+            .process(&raw_args.shell_manager, raw_args.ctrl_c.clone(), cp)?
+            .run()
     }
 }
 

crates/nu-cli/src/commands/date.rs

@@ -1,13 +1,13 @@
-use crate::data::{Dictionary, Value};
-use crate::errors::ShellError;
 use crate::prelude::*;
 use chrono::{DateTime, Local, Utc};
+use nu_errors::ShellError;
+use nu_protocol::{Dictionary, Value};
 
 use crate::commands::WholeStreamCommand;
-use crate::parser::registry::Signature;
 use chrono::{Datelike, TimeZone, Timelike};
 use core::fmt::Display;
 use indexmap::IndexMap;
+use nu_protocol::{Signature, UntaggedValue};
 
 pub struct Date;
 
@@ -17,7 +17,9 @@ impl WholeStreamCommand for Date {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("date").switch("utc").switch("local")
+        Signature::build("date")
+            .switch("utc", "use universal time (UTC)", Some('u'))
+            .switch("local", "use the local time", Some('l'))
     }
 
     fn usage(&self) -> &str {
@@ -33,26 +35,44 @@ impl WholeStreamCommand for Date {
     }
 }
 
-pub fn date_to_value<T: TimeZone>(dt: DateTime<T>, tag: Tag) -> Tagged<Value>
+pub fn date_to_value<T: TimeZone>(dt: DateTime<T>, tag: Tag) -> Value
 where
     T::Offset: Display,
 {
     let mut indexmap = IndexMap::new();
 
-    indexmap.insert("year".to_string(), Value::int(dt.year()).tagged(&tag));
-    indexmap.insert("month".to_string(), Value::int(dt.month()).tagged(&tag));
-    indexmap.insert("day".to_string(), Value::int(dt.day()).tagged(&tag));
-    indexmap.insert("hour".to_string(), Value::int(dt.hour()).tagged(&tag));
-    indexmap.insert("minute".to_string(), Value::int(dt.minute()).tagged(&tag));
-    indexmap.insert("second".to_string(), Value::int(dt.second()).tagged(&tag));
+    indexmap.insert(
+        "year".to_string(),
+        UntaggedValue::int(dt.year()).into_value(&tag),
+    );
+    indexmap.insert(
+        "month".to_string(),
+        UntaggedValue::int(dt.month()).into_value(&tag),
+    );
+    indexmap.insert(
+        "day".to_string(),
+        UntaggedValue::int(dt.day()).into_value(&tag),
+    );
+    indexmap.insert(
+        "hour".to_string(),
+        UntaggedValue::int(dt.hour()).into_value(&tag),
+    );
+    indexmap.insert(
+        "minute".to_string(),
+        UntaggedValue::int(dt.minute()).into_value(&tag),
+    );
+    indexmap.insert(
+        "second".to_string(),
+        UntaggedValue::int(dt.second()).into_value(&tag),
+    );
 
     let tz = dt.offset();
     indexmap.insert(
         "timezone".to_string(),
-        Value::string(format!("{}", tz)).tagged(&tag),
+        UntaggedValue::string(format!("{}", tz)).into_value(&tag),
     );
 
-    Value::Row(Dictionary::from(indexmap)).tagged(&tag)
+    UntaggedValue::Row(Dictionary::from(indexmap)).into_value(&tag)
 }
 
 pub fn date(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStream, ShellError> {
@@ -71,5 +91,5 @@ pub fn date(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStrea
 
     date_out.push_back(value);
 
-    Ok(date_out.to_output_stream())
+    Ok(futures::stream::iter(date_out).to_output_stream())
 }

crates/nu-cli/src/commands/debug.rs

@@ -0,0 +1,51 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{ReturnSuccess, Signature, UntaggedValue};
+
+pub struct Debug;
+
+#[derive(Deserialize)]
+pub struct DebugArgs {
+    raw: bool,
+}
+
+impl WholeStreamCommand for Debug {
+    fn name(&self) -> &str {
+        "debug"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("debug").switch("raw", "Prints the raw value representation.", Some('r'))
+    }
+
+    fn usage(&self) -> &str {
+        "Print the Rust debug representation of the values"
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, debug_value)?.run()
+    }
+}
+
+fn debug_value(
+    DebugArgs { raw }: DebugArgs,
+    RunnableContext { input, .. }: RunnableContext,
+) -> Result<impl ToOutputStream, ShellError> {
+    Ok(input
+        .values
+        .map(move |v| {
+            if raw {
+                ReturnSuccess::value(
+                    UntaggedValue::string(format!("{:#?}", v)).into_untagged_value(),
+                )
+            } else {
+                ReturnSuccess::debug_value(v)
+            }
+        })
+        .to_output_stream())
+}

crates/nu-cli/src/commands/default.rs

@@ -0,0 +1,76 @@
+use crate::commands::WholeStreamCommand;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_source::Tagged;
+use nu_value_ext::ValueExt;
+
+#[derive(Deserialize)]
+struct DefaultArgs {
+    column: Tagged<String>,
+    value: Value,
+}
+
+pub struct Default;
+
+impl WholeStreamCommand for Default {
+    fn name(&self) -> &str {
+        "default"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("default")
+            .required("column name", SyntaxShape::String, "the name of the column")
+            .required(
+                "column value",
+                SyntaxShape::Any,
+                "the value of the column to default",
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "Sets a default row's column if missing."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, default)?.run()
+    }
+}
+
+fn default(
+    DefaultArgs { column, value }: DefaultArgs,
+    RunnableContext { input, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let stream = input
+        .values
+        .map(move |item| {
+            let mut result = VecDeque::new();
+
+            let should_add = match item {
+                Value {
+                    value: UntaggedValue::Row(ref r),
+                    ..
+                } => r.get_data(&column.item).borrow().is_none(),
+                _ => false,
+            };
+
+            if should_add {
+                match item.insert_data_at_path(&column.item, value.clone()) {
+                    Some(new_value) => result.push_back(ReturnSuccess::value(new_value)),
+                    None => result.push_back(ReturnSuccess::value(item)),
+                }
+            } else {
+                result.push_back(ReturnSuccess::value(item));
+            }
+
+            futures::stream::iter(result)
+        })
+        .flatten();
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/du.rs

@@ -0,0 +1,376 @@
+extern crate filesize;
+
+use crate::commands::command::RunnablePerItemContext;
+use crate::prelude::*;
+use filesize::file_real_size_fast;
+use glob::*;
+use indexmap::map::IndexMap;
+use nu_errors::ShellError;
+use nu_protocol::{CallInfo, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_source::Tagged;
+use std::path::PathBuf;
+
+const NAME: &str = "du";
+const GLOB_PARAMS: MatchOptions = MatchOptions {
+    case_sensitive: true,
+    require_literal_separator: true,
+    require_literal_leading_dot: false,
+};
+
+pub struct Du;
+
+#[derive(Deserialize, Clone)]
+pub struct DuArgs {
+    path: Option<Tagged<PathBuf>>,
+    all: bool,
+    deref: bool,
+    exclude: Option<Tagged<String>>,
+    #[serde(rename = "max-depth")]
+    max_depth: Option<Tagged<u64>>,
+    #[serde(rename = "min-size")]
+    min_size: Option<Tagged<u64>>,
+}
+
+impl PerItemCommand for Du {
+    fn name(&self) -> &str {
+        NAME
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build(NAME)
+            .optional("path", SyntaxShape::Pattern, "starting directory")
+            .switch(
+                "all",
+                "Output file sizes as well as directory sizes",
+                Some('a'),
+            )
+            .switch(
+                "deref",
+                "Dereference symlinks to their targets for size",
+                Some('r'),
+            )
+            .named(
+                "exclude",
+                SyntaxShape::Pattern,
+                "Exclude these file names",
+                Some('x'),
+            )
+            .named(
+                "max-depth",
+                SyntaxShape::Int,
+                "Directory recursion limit",
+                Some('d'),
+            )
+            .named(
+                "min-size",
+                SyntaxShape::Int,
+                "Exclude files below this size",
+                Some('m'),
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "Find disk usage sizes of specified items"
+    }
+
+    fn run(
+        &self,
+        call_info: &CallInfo,
+        _registry: &CommandRegistry,
+        raw_args: &RawCommandArgs,
+        _input: Value,
+    ) -> Result<OutputStream, ShellError> {
+        call_info
+            .process(&raw_args.shell_manager, raw_args.ctrl_c.clone(), du)?
+            .run()
+    }
+}
+
+fn du(args: DuArgs, ctx: &RunnablePerItemContext) -> Result<OutputStream, ShellError> {
+    let tag = ctx.name.clone();
+
+    let exclude = args.exclude.map_or(Ok(None), move |x| {
+        Pattern::new(&x.item)
+            .map(Option::Some)
+            .map_err(|e| ShellError::labeled_error(e.msg, "glob error", x.tag.clone()))
+    })?;
+
+    let include_files = args.all;
+    let paths = match args.path {
+        Some(p) => {
+            let p = p.item.to_str().expect("Why isn't this encoded properly?");
+            glob::glob_with(p, GLOB_PARAMS)
+        }
+        None => glob::glob_with("*", GLOB_PARAMS),
+    }
+    .map_err(|e| ShellError::labeled_error(e.msg, "glob error", tag.clone()))?
+    .filter(move |p| {
+        if include_files {
+            true
+        } else {
+            match p {
+                Ok(f) if f.is_dir() => true,
+                Err(e) if e.path().is_dir() => true,
+                _ => false,
+            }
+        }
+    })
+    .map(|v| v.map_err(glob_err_into));
+
+    let ctrl_c = ctx.ctrl_c.clone();
+    let all = args.all;
+    let deref = args.deref;
+    let max_depth = args.max_depth.map(|f| f.item);
+    let min_size = args.min_size.map(|f| f.item);
+
+    let params = DirBuilder {
+        tag: tag.clone(),
+        min: min_size,
+        deref,
+        exclude,
+        all,
+    };
+
+    let stream = futures::stream::iter(paths)
+        .interruptible(ctrl_c)
+        .map(move |path| match path {
+            Ok(p) => {
+                if p.is_dir() {
+                    Ok(ReturnSuccess::Value(
+                        DirInfo::new(p, &params, max_depth).into(),
+                    ))
+                } else {
+                    FileInfo::new(p, deref, tag.clone()).map(|v| ReturnSuccess::Value(v.into()))
+                }
+            }
+            Err(e) => Err(e),
+        });
+
+    Ok(stream.to_output_stream())
+}
+
+struct DirBuilder {
+    tag: Tag,
+    min: Option<u64>,
+    deref: bool,
+    exclude: Option<Pattern>,
+    all: bool,
+}
+
+struct DirInfo {
+    dirs: Vec<DirInfo>,
+    files: Vec<FileInfo>,
+    errors: Vec<ShellError>,
+    size: u64,
+    blocks: u64,
+    path: PathBuf,
+    tag: Tag,
+}
+
+struct FileInfo {
+    path: PathBuf,
+    size: u64,
+    blocks: Option<u64>,
+    tag: Tag,
+}
+
+impl FileInfo {
+    fn new(path: impl Into<PathBuf>, deref: bool, tag: Tag) -> Result<Self, ShellError> {
+        let path = path.into();
+        let m = if deref {
+            std::fs::metadata(&path)
+        } else {
+            std::fs::symlink_metadata(&path)
+        };
+
+        match m {
+            Ok(d) => {
+                let block_size = file_real_size_fast(&path, &d).ok();
+
+                Ok(FileInfo {
+                    path,
+                    blocks: block_size,
+                    size: d.len(),
+                    tag,
+                })
+            }
+            Err(e) => Err(e.into()),
+        }
+    }
+}
+
+impl DirInfo {
+    fn new(path: impl Into<PathBuf>, params: &DirBuilder, depth: Option<u64>) -> Self {
+        let path = path.into();
+
+        let mut s = Self {
+            dirs: Vec::new(),
+            errors: Vec::new(),
+            files: Vec::new(),
+            size: 0,
+            blocks: 0,
+            tag: params.tag.clone(),
+            path,
+        };
+
+        match std::fs::read_dir(&s.path) {
+            Ok(d) => {
+                for f in d {
+                    match f {
+                        Ok(i) => match i.file_type() {
+                            Ok(t) if t.is_dir() => s = s.add_dir(i.path(), depth, &params),
+                            Ok(_t) => s = s.add_file(i.path(), &params),
+                            Err(e) => s = s.add_error(e.into()),
+                        },
+                        Err(e) => s = s.add_error(e.into()),
+                    }
+                }
+            }
+            Err(e) => s = s.add_error(e.into()),
+        }
+        s
+    }
+
+    fn add_dir(
+        mut self,
+        path: impl Into<PathBuf>,
+        mut depth: Option<u64>,
+        params: &DirBuilder,
+    ) -> Self {
+        if let Some(current) = depth {
+            if let Some(new) = current.checked_sub(1) {
+                depth = Some(new);
+            } else {
+                return self;
+            }
+        }
+
+        let d = DirInfo::new(path, &params, depth);
+        self.size += d.size;
+        self.blocks += d.blocks;
+        self.dirs.push(d);
+        self
+    }
+
+    fn add_file(mut self, f: impl Into<PathBuf>, params: &DirBuilder) -> Self {
+        let f = f.into();
+        let include = params
+            .exclude
+            .as_ref()
+            .map_or(true, |x| !x.matches_path(&f));
+        if include {
+            match FileInfo::new(f, params.deref, self.tag.clone()) {
+                Ok(file) => {
+                    let inc = params.min.map_or(true, |s| file.size >= s);
+                    if inc {
+                        self.size += file.size;
+                        self.blocks += file.blocks.unwrap_or(0);
+                        if params.all {
+                            self.files.push(file);
+                        }
+                    }
+                }
+                Err(e) => self = self.add_error(e),
+            }
+        }
+        self
+    }
+
+    fn add_error(mut self, e: ShellError) -> Self {
+        self.errors.push(e);
+        self
+    }
+}
+
+fn glob_err_into(e: GlobError) -> ShellError {
+    let e = e.into_error();
+    ShellError::from(e)
+}
+
+fn value_from_vec<V>(vec: Vec<V>, tag: &Tag) -> Value
+where
+    V: Into<Value>,
+{
+    if vec.is_empty() {
+        UntaggedValue::nothing()
+    } else {
+        let values = vec.into_iter().map(Into::into).collect::<Vec<Value>>();
+        UntaggedValue::Table(values)
+    }
+    .retag(tag)
+}
+
+impl From<DirInfo> for Value {
+    fn from(d: DirInfo) -> Self {
+        let mut r: IndexMap<String, Value> = IndexMap::new();
+
+        r.insert(
+            "path".to_string(),
+            UntaggedValue::path(d.path).retag(&d.tag),
+        );
+
+        r.insert(
+            "apparent".to_string(),
+            UntaggedValue::bytes(d.size).retag(&d.tag),
+        );
+
+        r.insert(
+            "physical".to_string(),
+            UntaggedValue::bytes(d.blocks).retag(&d.tag),
+        );
+
+        r.insert("directories".to_string(), value_from_vec(d.dirs, &d.tag));
+
+        r.insert("files".to_string(), value_from_vec(d.files, &d.tag));
+
+        if !d.errors.is_empty() {
+            let v = UntaggedValue::Table(
+                d.errors
+                    .into_iter()
+                    .map(move |e| UntaggedValue::Error(e).into_untagged_value())
+                    .collect::<Vec<Value>>(),
+            )
+            .retag(&d.tag);
+
+            r.insert("errors".to_string(), v);
+        }
+
+        Value {
+            value: UntaggedValue::row(r),
+            tag: d.tag,
+        }
+    }
+}
+
+impl From<FileInfo> for Value {
+    fn from(f: FileInfo) -> Self {
+        let mut r: IndexMap<String, Value> = IndexMap::new();
+
+        r.insert(
+            "path".to_string(),
+            UntaggedValue::path(f.path).retag(&f.tag),
+        );
+
+        r.insert(
+            "apparent".to_string(),
+            UntaggedValue::bytes(f.size).retag(&f.tag),
+        );
+
+        let b = f
+            .blocks
+            .map(UntaggedValue::bytes)
+            .unwrap_or_else(UntaggedValue::nothing)
+            .retag(&f.tag);
+
+        r.insert("physical".to_string(), b);
+
+        r.insert(
+            "directories".to_string(),
+            UntaggedValue::nothing().retag(&f.tag),
+        );
+
+        r.insert("files".to_string(), UntaggedValue::nothing().retag(&f.tag));
+
+        UntaggedValue::row(r).retag(&f.tag)
+    }
+}

crates/nu-cli/src/commands/echo.rs

@@ -0,0 +1,67 @@
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CallInfo, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+
+pub struct Echo;
+
+impl PerItemCommand for Echo {
+    fn name(&self) -> &str {
+        "echo"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("echo").rest(SyntaxShape::Any, "the values to echo")
+    }
+
+    fn usage(&self) -> &str {
+        "Echo the arguments back to the user."
+    }
+
+    fn run(
+        &self,
+        call_info: &CallInfo,
+        registry: &CommandRegistry,
+        raw_args: &RawCommandArgs,
+        _input: Value,
+    ) -> Result<OutputStream, ShellError> {
+        run(call_info, registry, raw_args)
+    }
+}
+
+fn run(
+    call_info: &CallInfo,
+    _registry: &CommandRegistry,
+    _raw_args: &RawCommandArgs,
+) -> Result<OutputStream, ShellError> {
+    let mut output = vec![];
+
+    if let Some(ref positional) = call_info.args.positional {
+        for i in positional {
+            match i.as_string() {
+                Ok(s) => {
+                    output.push(Ok(ReturnSuccess::Value(
+                        UntaggedValue::string(s).into_value(i.tag.clone()),
+                    )));
+                }
+                _ => match i {
+                    Value {
+                        value: UntaggedValue::Table(table),
+                        ..
+                    } => {
+                        for value in table {
+                            output.push(Ok(ReturnSuccess::Value(value.clone())));
+                        }
+                    }
+                    _ => {
+                        output.push(Ok(ReturnSuccess::Value(i.clone())));
+                    }
+                },
+            }
+        }
+    }
+
+    // TODO: This whole block can probably be replaced with `.map()`
+    let stream = futures::stream::iter(output);
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/edit.rs

@@ -0,0 +1,72 @@
+use crate::commands::PerItemCommand;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CallInfo, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_value_ext::ValueExt;
+
+pub struct Edit;
+
+impl PerItemCommand for Edit {
+    fn name(&self) -> &str {
+        "edit"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("edit")
+            .required(
+                "Field",
+                SyntaxShape::ColumnPath,
+                "the name of the column to edit",
+            )
+            .required(
+                "Value",
+                SyntaxShape::String,
+                "the new value to give the cell(s)",
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "Edit an existing column to have a new value."
+    }
+
+    fn run(
+        &self,
+        call_info: &CallInfo,
+        _registry: &CommandRegistry,
+        _raw_args: &RawCommandArgs,
+        value: Value,
+    ) -> Result<OutputStream, ShellError> {
+        let value_tag = value.tag();
+        let field = call_info.args.expect_nth(0)?.as_column_path()?;
+        let replacement = call_info.args.expect_nth(1)?.tagged_unknown();
+
+        let stream = match value {
+            obj
+            @
+            Value {
+                value: UntaggedValue::Row(_),
+                ..
+            } => match obj.replace_data_at_column_path(&field, replacement.item.clone()) {
+                Some(v) => futures::stream::iter(vec![Ok(ReturnSuccess::Value(v))]),
+                None => {
+                    return Err(ShellError::labeled_error(
+                        "edit could not find place to insert column",
+                        "column name",
+                        &field.tag,
+                    ))
+                }
+            },
+
+            _ => {
+                return Err(ShellError::labeled_error(
+                    "Unrecognized type in stream",
+                    "original value",
+                    value_tag,
+                ))
+            }
+        };
+
+        Ok(stream.to_output_stream())
+    }
+}

crates/nu-cli/src/commands/enter.rs

@@ -1,11 +1,11 @@
-use crate::commands::command::CommandAction;
 use crate::commands::PerItemCommand;
 use crate::commands::UnevaluatedCallInfo;
-use crate::data::meta::Span;
-use crate::errors::ShellError;
-use crate::parser::registry;
+use crate::context::CommandRegistry;
 use crate::prelude::*;
-use std::path::PathBuf;
+use nu_errors::ShellError;
+use nu_protocol::{
+    CallInfo, CommandAction, Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
+};
 
 pub struct Enter;
 
@@ -14,8 +14,12 @@ impl PerItemCommand for Enter {
         "enter"
     }
 
-    fn signature(&self) -> registry::Signature {
-        Signature::build("enter").required("location", SyntaxShape::Path)
+    fn signature(&self) -> Signature {
+        Signature::build("enter").required(
+            "location",
+            SyntaxShape::Path,
+            "the location to create a new shell from",
+        )
     }
 
     fn usage(&self) -> &str {
@@ -25,37 +29,42 @@ impl PerItemCommand for Enter {
     fn run(
         &self,
         call_info: &CallInfo,
-        registry: &registry::CommandRegistry,
+        registry: &CommandRegistry,
         raw_args: &RawCommandArgs,
-        _input: Tagged<Value>,
+        _input: Value,
     ) -> Result<OutputStream, ShellError> {
         let registry = registry.clone();
         let raw_args = raw_args.clone();
         match call_info.args.expect_nth(0)? {
-            Tagged {
-                item: Value::Primitive(Primitive::Path(location)),
+            Value {
+                value: UntaggedValue::Primitive(Primitive::Path(location)),
+                tag,
                 ..
             } => {
                 let location_string = location.display().to_string();
                 let location_clone = location_string.clone();
+                let tag_clone = tag.clone();
 
-                if location.starts_with("help") {
-                    let spec = location_string.split(":").collect::<Vec<&str>>();
+                if location_string.starts_with("help") {
+                    let spec = location_string.split(':').collect::<Vec<&str>>();
 
-                    let (_, command) = (spec[0], spec[1]);
+                    if spec.len() == 2 {
+                        let (_, command) = (spec[0], spec[1]);
 
-                    if registry.has(command) {
-                        Ok(vec![Ok(ReturnSuccess::Action(CommandAction::EnterHelpShell(
-                            Value::string(command).tagged(Tag::unknown()),
-                        )))]
-                        .into())
-                    } else {
-                        Ok(vec![Ok(ReturnSuccess::Action(CommandAction::EnterHelpShell(
-                            Value::nothing().tagged(Tag::unknown()),
-                        )))]
-                        .into())
+                        if registry.has(command) {
+                            return Ok(vec![Ok(ReturnSuccess::Action(
+                                CommandAction::EnterHelpShell(
+                                    UntaggedValue::string(command).into_value(Tag::unknown()),
+                                ),
+                            ))]
+                            .into());
+                        }
                     }
-                } else if PathBuf::from(location).is_dir() {
+                    Ok(vec![Ok(ReturnSuccess::Action(CommandAction::EnterHelpShell(
+                        UntaggedValue::nothing().into_value(Tag::unknown()),
+                    )))]
+                    .into())
+                } else if location.is_dir() {
                     Ok(vec![Ok(ReturnSuccess::Action(CommandAction::EnterShell(
                         location_clone,
                     )))]
@@ -71,13 +80,12 @@ impl PerItemCommand for Enter {
                             crate::commands::open::fetch(
                                 &full_path,
                                 &location_clone,
-                                Span::unknown(),
-                            )
-                            .await.unwrap();
+                                tag_clone.span,
+                            ).await?;
 
                         match contents {
-                            Value::Primitive(Primitive::String(_)) => {
-                                let tagged_contents = contents.tagged(&contents_tag);
+                            UntaggedValue::Primitive(Primitive::String(_)) => {
+                                let tagged_contents = contents.into_value(&contents_tag);
 
                                 if let Some(extension) = file_extension {
                                     let command_name = format!("from-{}", extension);
@@ -89,10 +97,11 @@ impl PerItemCommand for Enter {
                                             ctrl_c: raw_args.ctrl_c,
                                             shell_manager: raw_args.shell_manager,
                                             call_info: UnevaluatedCallInfo {
-                                                args: crate::parser::hir::Call {
+                                                args: nu_parser::hir::Call {
                                                     head: raw_args.call_info.args.head,
                                                     positional: None,
                                                     named: None,
+                                                    span: Span::unknown()
                                                 },
                                                 source: raw_args.call_info.source,
                                                 name_tag: raw_args.call_info.name_tag,
@@ -101,19 +110,18 @@ impl PerItemCommand for Enter {
                                         let mut result = converter.run(
                                             new_args.with_input(vec![tagged_contents]),
                                             &registry,
-                                            false
                                         );
                                         let result_vec: Vec<Result<ReturnSuccess, ShellError>> =
                                             result.drain_vec().await;
                                         for res in result_vec {
                                             match res {
-                                                Ok(ReturnSuccess::Value(Tagged {
-                                                    item,
+                                                Ok(ReturnSuccess::Value(Value {
+                                                    value,
                                                     ..
                                                 })) => {
                                                     yield Ok(ReturnSuccess::Action(CommandAction::EnterValueShell(
-                                                        Tagged {
-                                                            item,
+                                                        Value {
+                                                            value,
                                                             tag: contents_tag.clone(),
                                                         })));
                                                 }
@@ -128,7 +136,7 @@ impl PerItemCommand for Enter {
                                 }
                             }
                             _ => {
-                                let tagged_contents = contents.tagged(contents_tag);
+                                let tagged_contents = contents.into_value(contents_tag);
 
                                 yield Ok(ReturnSuccess::Action(CommandAction::EnterValueShell(tagged_contents)));
                             }

crates/nu-cli/src/commands/evaluate_by.rs

@@ -0,0 +1,72 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use crate::utils::data_processing::{evaluate, fetch};
+use nu_errors::ShellError;
+use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_source::{SpannedItem, Tagged};
+use nu_value_ext::ValueExt;
+
+pub struct EvaluateBy;
+
+#[derive(Deserialize)]
+pub struct EvaluateByArgs {
+    evaluate_with: Option<Tagged<String>>,
+}
+
+impl WholeStreamCommand for EvaluateBy {
+    fn name(&self) -> &str {
+        "evaluate-by"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("evaluate-by").named(
+            "evaluate_with",
+            SyntaxShape::String,
+            "the name of the column to evaluate by",
+            Some('w'),
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Creates a new table with the data from the tables rows evaluated by the column given."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, evaluate_by)?.run()
+    }
+}
+
+pub fn evaluate_by(
+    EvaluateByArgs { evaluate_with }: EvaluateByArgs,
+    RunnableContext { input, name, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let stream = async_stream! {
+        let values: Vec<Value> = input.values.collect().await;
+
+        if values.is_empty() {
+            yield Err(ShellError::labeled_error(
+                    "Expected table from pipeline",
+                    "requires a table input",
+                    name
+                ))
+        } else {
+
+            let evaluate_with = if let Some(evaluator) = evaluate_with {
+                Some(evaluator.item().clone())
+            } else {
+                None
+            };
+
+            match evaluate(&values[0], evaluate_with, name) {
+                Ok(evaluated) => yield ReturnSuccess::value(evaluated),
+                Err(err) => yield Err(err)
+            }
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/exit.rs

@@ -1,7 +1,8 @@
-use crate::commands::command::{CommandAction, WholeStreamCommand};
-use crate::errors::ShellError;
-use crate::parser::registry::{CommandRegistry, Signature};
+use crate::commands::command::WholeStreamCommand;
+use crate::context::CommandRegistry;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CommandAction, ReturnSuccess, Signature};
 
 pub struct Exit;
 
@@ -11,7 +12,7 @@ impl WholeStreamCommand for Exit {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("exit").switch("now")
+        Signature::build("exit").switch("now", "exit out of the shell immediately", Some('n'))
     }
 
     fn usage(&self) -> &str {

crates/nu-cli/src/commands/first.rs

@@ -1,13 +1,15 @@
 use crate::commands::WholeStreamCommand;
-use crate::errors::ShellError;
-use crate::parser::CommandRegistry;
+use crate::context::CommandRegistry;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Signature, SyntaxShape};
+use nu_source::Tagged;
 
 pub struct First;
 
 #[derive(Deserialize)]
 pub struct FirstArgs {
-    rows: Option<Tagged<u64>>,
+    rows: Option<Tagged<usize>>,
 }
 
 impl WholeStreamCommand for First {
@@ -16,7 +18,11 @@ impl WholeStreamCommand for First {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("first").optional("rows", SyntaxShape::Int)
+        Signature::build("first").optional(
+            "rows",
+            SyntaxShape::Int,
+            "starting from the front, the number of rows to return",
+        )
     }
 
     fn usage(&self) -> &str {

crates/nu-cli/src/commands/format.rs

@@ -0,0 +1,157 @@
+use crate::commands::PerItemCommand;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{
+    CallInfo, ColumnPath, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
+};
+use nu_source::Tagged;
+use nu_value_ext::{as_column_path, get_data_by_column_path};
+use std::borrow::Borrow;
+
+use nom::{
+    bytes::complete::{tag, take_while},
+    IResult,
+};
+
+pub struct Format;
+
+impl PerItemCommand for Format {
+    fn name(&self) -> &str {
+        "format"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("format").required(
+            "pattern",
+            SyntaxShape::Any,
+            "the pattern to output. Eg) \"{foo}: {bar}\"",
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Format columns into a string using a simple pattern."
+    }
+
+    fn run(
+        &self,
+        call_info: &CallInfo,
+        _registry: &CommandRegistry,
+        _raw_args: &RawCommandArgs,
+        value: Value,
+    ) -> Result<OutputStream, ShellError> {
+        //let value_tag = value.tag();
+        let pattern = call_info.args.expect_nth(0)?;
+        let pattern_tag = pattern.tag.clone();
+        let pattern = pattern.as_string()?;
+
+        let format_pattern = format(&pattern).map_err(|_| {
+            ShellError::labeled_error(
+                "Could not create format pattern",
+                "could not create format pattern",
+                &pattern_tag,
+            )
+        })?;
+        let commands = format_pattern.1;
+
+        let output = match value {
+            value
+            @
+            Value {
+                value: UntaggedValue::Row(_),
+                ..
+            } => {
+                let mut output = String::new();
+
+                for command in &commands {
+                    match command {
+                        FormatCommand::Text(s) => {
+                            output.push_str(s);
+                        }
+                        FormatCommand::Column(c) => {
+                            let key = to_column_path(&c, &pattern_tag)?;
+
+                            let fetcher = get_data_by_column_path(
+                                &value,
+                                &key,
+                                Box::new(move |(_, _, error)| error),
+                            );
+
+                            if let Ok(c) = fetcher {
+                                output
+                                    .push_str(&value::format_leaf(c.borrow()).plain_string(100_000))
+                            }
+                            // That column doesn't match, so don't emit anything
+                        }
+                    }
+                }
+
+                output
+            }
+            _ => String::new(),
+        };
+
+        Ok(futures::stream::iter(vec![ReturnSuccess::value(
+            UntaggedValue::string(output).into_untagged_value(),
+        )])
+        .to_output_stream())
+    }
+}
+
+#[derive(Debug)]
+enum FormatCommand {
+    Text(String),
+    Column(String),
+}
+
+fn format(input: &str) -> IResult<&str, Vec<FormatCommand>> {
+    let mut output = vec![];
+
+    let mut loop_input = input;
+    loop {
+        let (input, before) = take_while(|c| c != '{')(loop_input)?;
+        if !before.is_empty() {
+            output.push(FormatCommand::Text(before.to_string()));
+        }
+        if input != "" {
+            // Look for column as we're now at one
+            let (input, _) = tag("{")(input)?;
+            let (input, column) = take_while(|c| c != '}')(input)?;
+            let (input, _) = tag("}")(input)?;
+
+            output.push(FormatCommand::Column(column.to_string()));
+            loop_input = input;
+        } else {
+            loop_input = input;
+        }
+        if loop_input == "" {
+            break;
+        }
+    }
+
+    Ok((loop_input, output))
+}
+
+fn to_column_path(
+    path_members: &str,
+    tag: impl Into<Tag>,
+) -> Result<Tagged<ColumnPath>, ShellError> {
+    let tag = tag.into();
+
+    as_column_path(
+        &UntaggedValue::Table(
+            path_members
+                .split('.')
+                .map(|x| {
+                    let member = match x.parse::<u64>() {
+                        Ok(v) => UntaggedValue::int(v),
+                        Err(_) => UntaggedValue::string(x),
+                    };
+
+                    member.into_value(&tag)
+                })
+                .collect(),
+        )
+        .into_value(&tag),
+    )
+}

crates/nu-cli/src/commands/from_bson.rs

@@ -1,8 +1,9 @@
 use crate::commands::WholeStreamCommand;
-use crate::data::{Primitive, TaggedDictBuilder, Value};
-use crate::errors::ExpectedRange;
 use crate::prelude::*;
 use bson::{decode_document, spec::BinarySubtype, Bson};
+use nu_errors::{ExpectedRange, ShellError};
+use nu_protocol::{Primitive, ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue, Value};
+use nu_source::SpannedItem;
 use std::str::FromStr;
 
 pub struct FromBSON;
@@ -29,7 +30,7 @@ impl WholeStreamCommand for FromBSON {
     }
 }
 
-fn bson_array(input: &Vec<Bson>, tag: Tag) -> Result<Vec<Tagged<Value>>, ShellError> {
+fn bson_array(input: &[Bson], tag: Tag) -> Result<Vec<Value>, ShellError> {
     let mut out = vec![];
 
     for value in input {
@@ -39,109 +40,114 @@ fn bson_array(input: &Vec<Bson>, tag: Tag) -> Result<Vec<Tagged<Value>>, ShellEr
     Ok(out)
 }
 
-fn convert_bson_value_to_nu_value(
-    v: &Bson,
-    tag: impl Into<Tag>,
-) -> Result<Tagged<Value>, ShellError> {
+fn convert_bson_value_to_nu_value(v: &Bson, tag: impl Into<Tag>) -> Result<Value, ShellError> {
     let tag = tag.into();
+    let span = tag.span;
 
     Ok(match v {
-        Bson::FloatingPoint(n) => Value::Primitive(Primitive::from(*n)).tagged(&tag),
-        Bson::String(s) => Value::Primitive(Primitive::String(String::from(s))).tagged(&tag),
-        Bson::Array(a) => Value::Table(bson_array(a, tag.clone())?).tagged(&tag),
+        Bson::FloatingPoint(n) => UntaggedValue::Primitive(Primitive::from(*n)).into_value(&tag),
+        Bson::String(s) => {
+            UntaggedValue::Primitive(Primitive::String(String::from(s))).into_value(&tag)
+        }
+        Bson::Array(a) => UntaggedValue::Table(bson_array(a, tag.clone())?).into_value(&tag),
         Bson::Document(doc) => {
             let mut collected = TaggedDictBuilder::new(tag.clone());
             for (k, v) in doc.iter() {
-                collected.insert_tagged(k.clone(), convert_bson_value_to_nu_value(v, &tag)?);
+                collected.insert_value(k.clone(), convert_bson_value_to_nu_value(v, &tag)?);
             }
 
-            collected.into_tagged_value()
+            collected.into_value()
         }
-        Bson::Boolean(b) => Value::Primitive(Primitive::Boolean(*b)).tagged(&tag),
-        Bson::Null => Value::Primitive(Primitive::Nothing).tagged(&tag),
+        Bson::Boolean(b) => UntaggedValue::Primitive(Primitive::Boolean(*b)).into_value(&tag),
+        Bson::Null => UntaggedValue::Primitive(Primitive::Nothing).into_value(&tag),
         Bson::RegExp(r, opts) => {
             let mut collected = TaggedDictBuilder::new(tag.clone());
-            collected.insert_tagged(
+            collected.insert_value(
                 "$regex".to_string(),
-                Value::Primitive(Primitive::String(String::from(r))).tagged(&tag),
+                UntaggedValue::Primitive(Primitive::String(String::from(r))).into_value(&tag),
             );
-            collected.insert_tagged(
+            collected.insert_value(
                 "$options".to_string(),
-                Value::Primitive(Primitive::String(String::from(opts))).tagged(&tag),
+                UntaggedValue::Primitive(Primitive::String(String::from(opts))).into_value(&tag),
             );
-            collected.into_tagged_value()
+            collected.into_value()
         }
-        Bson::I32(n) => Value::number(n).tagged(&tag),
-        Bson::I64(n) => Value::number(n).tagged(&tag),
+        Bson::I32(n) => UntaggedValue::int(*n).into_value(&tag),
+        Bson::I64(n) => UntaggedValue::int(*n).into_value(&tag),
         Bson::Decimal128(n) => {
             // TODO: this really isn't great, and we should update this to do a higher
             // fidelity translation
             let decimal = BigDecimal::from_str(&format!("{}", n)).map_err(|_| {
                 ShellError::range_error(
                     ExpectedRange::BigDecimal,
-                    &n.tagged(&tag),
-                    format!("converting BSON Decimal128 to BigDecimal"),
+                    &n.spanned(span),
+                    "converting BSON Decimal128 to BigDecimal".to_owned(),
                 )
             })?;
-            Value::Primitive(Primitive::Decimal(decimal)).tagged(&tag)
+            UntaggedValue::Primitive(Primitive::Decimal(decimal)).into_value(&tag)
         }
         Bson::JavaScriptCode(js) => {
             let mut collected = TaggedDictBuilder::new(tag.clone());
-            collected.insert_tagged(
+            collected.insert_value(
                 "$javascript".to_string(),
-                Value::Primitive(Primitive::String(String::from(js))).tagged(&tag),
+                UntaggedValue::Primitive(Primitive::String(String::from(js))).into_value(&tag),
             );
-            collected.into_tagged_value()
+            collected.into_value()
         }
         Bson::JavaScriptCodeWithScope(js, doc) => {
             let mut collected = TaggedDictBuilder::new(tag.clone());
-            collected.insert_tagged(
+            collected.insert_value(
                 "$javascript".to_string(),
-                Value::Primitive(Primitive::String(String::from(js))).tagged(&tag),
+                UntaggedValue::Primitive(Primitive::String(String::from(js))).into_value(&tag),
             );
-            collected.insert_tagged(
+            collected.insert_value(
                 "$scope".to_string(),
-                convert_bson_value_to_nu_value(&Bson::Document(doc.to_owned()), tag.clone())?,
+                convert_bson_value_to_nu_value(&Bson::Document(doc.to_owned()), tag)?,
             );
-            collected.into_tagged_value()
+            collected.into_value()
         }
         Bson::TimeStamp(ts) => {
             let mut collected = TaggedDictBuilder::new(tag.clone());
-            collected.insert_tagged("$timestamp".to_string(), Value::number(ts).tagged(&tag));
-            collected.into_tagged_value()
+            collected.insert_value(
+                "$timestamp".to_string(),
+                UntaggedValue::int(*ts).into_value(&tag),
+            );
+            collected.into_value()
         }
         Bson::Binary(bst, bytes) => {
             let mut collected = TaggedDictBuilder::new(tag.clone());
-            collected.insert_tagged(
+            collected.insert_value(
                 "$binary_subtype".to_string(),
                 match bst {
-                    BinarySubtype::UserDefined(u) => Value::number(u),
-                    _ => Value::Primitive(Primitive::String(binary_subtype_to_string(*bst))),
+                    BinarySubtype::UserDefined(u) => UntaggedValue::int(*u),
+                    _ => {
+                        UntaggedValue::Primitive(Primitive::String(binary_subtype_to_string(*bst)))
+                    }
                 }
-                .tagged(&tag),
+                .into_value(&tag),
             );
-            collected.insert_tagged(
+            collected.insert_value(
                 "$binary".to_string(),
-                Value::Primitive(Primitive::Binary(bytes.to_owned())).tagged(&tag),
+                UntaggedValue::Primitive(Primitive::Binary(bytes.to_owned())).into_value(&tag),
             );
-            collected.into_tagged_value()
+            collected.into_value()
         }
         Bson::ObjectId(obj_id) => {
             let mut collected = TaggedDictBuilder::new(tag.clone());
-            collected.insert_tagged(
+            collected.insert_value(
                 "$object_id".to_string(),
-                Value::Primitive(Primitive::String(obj_id.to_hex())).tagged(&tag),
+                UntaggedValue::Primitive(Primitive::String(obj_id.to_hex())).into_value(&tag),
             );
-            collected.into_tagged_value()
+            collected.into_value()
         }
-        Bson::UtcDatetime(dt) => Value::Primitive(Primitive::Date(*dt)).tagged(&tag),
+        Bson::UtcDatetime(dt) => UntaggedValue::Primitive(Primitive::Date(*dt)).into_value(&tag),
         Bson::Symbol(s) => {
             let mut collected = TaggedDictBuilder::new(tag.clone());
-            collected.insert_tagged(
+            collected.insert_value(
                 "$symbol".to_string(),
-                Value::Primitive(Primitive::String(String::from(s))).tagged(&tag),
+                UntaggedValue::Primitive(Primitive::String(String::from(s))).into_value(&tag),
             );
-            collected.into_tagged_value()
+            collected.into_value()
         }
     })
 }
@@ -183,10 +189,7 @@ impl std::io::Read for BytesReader {
     }
 }
 
-pub fn from_bson_bytes_to_value(
-    bytes: Vec<u8>,
-    tag: impl Into<Tag>,
-) -> Result<Tagged<Value>, ShellError> {
+pub fn from_bson_bytes_to_value(bytes: Vec<u8>, tag: impl Into<Tag>) -> Result<Value, ShellError> {
     let mut docs = Vec::new();
     let mut b_reader = BytesReader::new(bytes);
     while let Ok(v) = decode_document(&mut b_reader) {
@@ -202,32 +205,18 @@ fn from_bson(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStre
     let input = args.input;
 
     let stream = async_stream! {
-        let values: Vec<Tagged<Value>> = input.values.collect().await;
+        let bytes = input.collect_binary(tag.clone()).await?;
 
-        for value in values {
-            let value_tag = value.tag();
-            match value.item {
-                Value::Primitive(Primitive::Binary(vb)) =>
-                    match from_bson_bytes_to_value(vb, tag.clone()) {
-                        Ok(x) => yield ReturnSuccess::value(x),
-                        Err(_) => {
-                            yield Err(ShellError::labeled_error_with_secondary(
-                                "Could not parse as BSON",
-                                "input cannot be parsed as BSON",
-                                tag.clone(),
-                                "value originates from here",
-                                value_tag,
-                            ))
-                        }
-                    }
-                _ => yield Err(ShellError::labeled_error_with_secondary(
-                    "Expected a string from pipeline",
-                    "requires string input",
+        match from_bson_bytes_to_value(bytes.item, tag.clone()) {
+            Ok(x) => yield ReturnSuccess::value(x),
+            Err(_) => {
+                yield Err(ShellError::labeled_error_with_secondary(
+                    "Could not parse as BSON",
+                    "input cannot be parsed as BSON",
                     tag.clone(),
                     "value originates from here",
-                    value_tag,
-                )),
-
+                    bytes.tag,
+                ))
             }
         }
     };

crates/nu-cli/src/commands/from_csv.rs

@@ -0,0 +1,79 @@
+use crate::commands::from_delimited_data::from_delimited_data;
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, Signature, SyntaxShape, UntaggedValue, Value};
+
+pub struct FromCSV;
+
+#[derive(Deserialize)]
+pub struct FromCSVArgs {
+    headerless: bool,
+    separator: Option<Value>,
+}
+
+impl WholeStreamCommand for FromCSV {
+    fn name(&self) -> &str {
+        "from-csv"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("from-csv")
+            .named(
+                "separator",
+                SyntaxShape::String,
+                "a character to separate columns, defaults to ','",
+                Some('s'),
+            )
+            .switch(
+                "headerless",
+                "don't treat the first row as column names",
+                None,
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "Parse text as .csv and create table."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, from_csv)?.run()
+    }
+}
+
+fn from_csv(
+    FromCSVArgs {
+        headerless,
+        separator,
+    }: FromCSVArgs,
+    runnable_context: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let sep = match separator {
+        Some(Value {
+            value: UntaggedValue::Primitive(Primitive::String(s)),
+            tag,
+            ..
+        }) => {
+            if s == r"\t" {
+                '\t'
+            } else {
+                let vec_s: Vec<char> = s.chars().collect();
+                if vec_s.len() != 1 {
+                    return Err(ShellError::labeled_error(
+                        "Expected a single separator char from --separator",
+                        "requires a single character string input",
+                        tag,
+                    ));
+                };
+                vec_s[0]
+            }
+        }
+        _ => ',',
+    };
+
+    from_delimited_data(headerless, sep, "CSV", runnable_context)
+}

crates/nu-cli/src/commands/from_delimited_data.rs

@@ -0,0 +1,169 @@
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_parser::hir::syntax_shape::{ExpandContext, SignatureRegistry};
+use nu_parser::utils::{parse_line_with_separator as parse, LineSeparatedShape};
+use nu_parser::TokensIterator;
+use nu_protocol::{ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue, Value};
+use nu_source::nom_input;
+
+use derive_new::new;
+
+pub fn from_delimited_data(
+    headerless: bool,
+    sep: char,
+    format_name: &'static str,
+    RunnableContext { input, name, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let name_tag = name;
+
+    let stream = async_stream! {
+        let concat_string = input.collect_string(name_tag.clone()).await?;
+
+        match from_delimited_string_to_value(concat_string.item, headerless, sep, name_tag.clone()) {
+            Ok(rows) => {
+                for row in rows {
+                    match row {
+                        Value { value: UntaggedValue::Table(list), .. } => {
+                            for l in list {
+                                yield ReturnSuccess::value(l);
+                            }
+                        }
+                        x => yield ReturnSuccess::value(x),
+                    }
+                }
+            },
+            Err(err) => {
+                let line_one = format!("Could not parse as {}", format_name);
+                let line_two = format!("input cannot be parsed as {}", format_name);
+                yield Err(ShellError::labeled_error_with_secondary(
+                    line_one,
+                    line_two,
+                    name_tag.clone(),
+                    "value originates from here",
+                    concat_string.tag,
+                ))
+            } ,
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}
+
+#[derive(Debug, Clone, new)]
+pub struct EmptyRegistry {
+    #[new(default)]
+    signatures: indexmap::IndexMap<String, Signature>,
+}
+
+impl EmptyRegistry {}
+
+impl SignatureRegistry for EmptyRegistry {
+    fn has(&self, _name: &str) -> bool {
+        false
+    }
+    fn get(&self, _name: &str) -> Option<Signature> {
+        None
+    }
+    fn clone_box(&self) -> Box<dyn SignatureRegistry> {
+        Box::new(self.clone())
+    }
+}
+
+fn from_delimited_string_to_value(
+    s: String,
+    headerless: bool,
+    sep: char,
+    tag: impl Into<Tag>,
+) -> Result<Vec<Value>, ShellError> {
+    let tag = tag.into();
+
+    let mut entries = s.lines();
+
+    let mut fields = vec![];
+    let mut out = vec![];
+
+    if let Some(first_entry) = entries.next() {
+        let tokens = match parse(&sep.to_string(), nom_input(first_entry)) {
+            Ok((_, tokens)) => tokens,
+            Err(err) => return Err(ShellError::parse_error(err)),
+        };
+
+        let tokens_span = tokens.span;
+        let source: nu_source::Text = tokens_span.slice(&first_entry).into();
+
+        if !headerless {
+            fields = tokens
+                .item
+                .iter()
+                .filter(|token| !token.is_separator())
+                .map(|field| field.source(&source).to_string())
+                .collect::<Vec<_>>();
+        }
+
+        let registry = Box::new(EmptyRegistry::new());
+        let ctx = ExpandContext::new(registry, &source, None);
+
+        let mut iterator = TokensIterator::new(&tokens.item, ctx, tokens_span);
+        let (results, tokens_identified) = iterator.expand(LineSeparatedShape);
+        let results = results?;
+
+        let mut row = TaggedDictBuilder::new(&tag);
+
+        if headerless {
+            let fallback_columns = (1..=tokens_identified)
+                .map(|i| format!("Column{}", i))
+                .collect::<Vec<String>>();
+
+            for (idx, field) in results.into_iter().enumerate() {
+                let key = if headerless {
+                    &fallback_columns[idx]
+                } else {
+                    &fields[idx]
+                };
+
+                row.insert_value(key, field.into_value(&tag));
+            }
+
+            out.push(row.into_value())
+        }
+    }
+
+    for entry in entries {
+        let tokens = match parse(&sep.to_string(), nom_input(entry)) {
+            Ok((_, tokens)) => tokens,
+            Err(err) => return Err(ShellError::parse_error(err)),
+        };
+        let tokens_span = tokens.span;
+
+        let source: nu_source::Text = tokens_span.slice(&entry).into();
+        let registry = Box::new(EmptyRegistry::new());
+        let ctx = ExpandContext::new(registry, &source, None);
+
+        let mut iterator = TokensIterator::new(&tokens.item, ctx, tokens_span);
+        let (results, tokens_identified) = iterator.expand(LineSeparatedShape);
+        let results = results?;
+
+        let mut row = TaggedDictBuilder::new(&tag);
+
+        let fallback_columns = (1..=tokens_identified)
+            .map(|i| format!("Column{}", i))
+            .collect::<Vec<String>>();
+
+        for (idx, field) in results.into_iter().enumerate() {
+            let key = if headerless {
+                &fallback_columns[idx]
+            } else {
+                match fields.get(idx) {
+                    Some(key) => key,
+                    None => &fallback_columns[idx],
+                }
+            };
+
+            row.insert_value(key, field.into_value(&tag));
+        }
+
+        out.push(row.into_value())
+    }
+
+    Ok(out)
+}

crates/nu-cli/src/commands/from_ics.rs

@@ -0,0 +1,240 @@
+extern crate ical;
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use ical::parser::ical::component::*;
+use ical::property::Property;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue, Value};
+use std::io::BufReader;
+
+pub struct FromIcs;
+
+impl WholeStreamCommand for FromIcs {
+    fn name(&self) -> &str {
+        "from-ics"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("from-ics")
+    }
+
+    fn usage(&self) -> &str {
+        "Parse text as .ics and create table."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        from_ics(args, registry)
+    }
+}
+
+fn from_ics(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStream, ShellError> {
+    let args = args.evaluate_once(registry)?;
+    let tag = args.name_tag();
+    let input = args.input;
+
+    let stream = async_stream! {
+        let input_string = input.collect_string(tag.clone()).await?.item;
+        let input_bytes = input_string.as_bytes();
+        let buf_reader = BufReader::new(input_bytes);
+        let parser = ical::IcalParser::new(buf_reader);
+
+        for calendar in parser {
+            match calendar {
+                Ok(c) => yield ReturnSuccess::value(calendar_to_value(c, tag.clone())),
+                Err(_) => yield Err(ShellError::labeled_error(
+                    "Could not parse as .ics",
+                    "input cannot be parsed as .ics",
+                    tag.clone()
+                )),
+            }
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}
+
+fn calendar_to_value(calendar: IcalCalendar, tag: Tag) -> Value {
+    let mut row = TaggedDictBuilder::new(tag.clone());
+
+    row.insert_untagged(
+        "properties",
+        properties_to_value(calendar.properties, tag.clone()),
+    );
+    row.insert_untagged("events", events_to_value(calendar.events, tag.clone()));
+    row.insert_untagged("alarms", alarms_to_value(calendar.alarms, tag.clone()));
+    row.insert_untagged("to-Dos", todos_to_value(calendar.todos, tag.clone()));
+    row.insert_untagged(
+        "journals",
+        journals_to_value(calendar.journals, tag.clone()),
+    );
+    row.insert_untagged(
+        "free-busys",
+        free_busys_to_value(calendar.free_busys, tag.clone()),
+    );
+    row.insert_untagged("timezones", timezones_to_value(calendar.timezones, tag));
+
+    row.into_value()
+}
+
+fn events_to_value(events: Vec<IcalEvent>, tag: Tag) -> UntaggedValue {
+    UntaggedValue::table(
+        &events
+            .into_iter()
+            .map(|event| {
+                let mut row = TaggedDictBuilder::new(tag.clone());
+                row.insert_untagged(
+                    "properties",
+                    properties_to_value(event.properties, tag.clone()),
+                );
+                row.insert_untagged("alarms", alarms_to_value(event.alarms, tag.clone()));
+                row.into_value()
+            })
+            .collect::<Vec<Value>>(),
+    )
+}
+
+fn alarms_to_value(alarms: Vec<IcalAlarm>, tag: Tag) -> UntaggedValue {
+    UntaggedValue::table(
+        &alarms
+            .into_iter()
+            .map(|alarm| {
+                let mut row = TaggedDictBuilder::new(tag.clone());
+                row.insert_untagged(
+                    "properties",
+                    properties_to_value(alarm.properties, tag.clone()),
+                );
+                row.into_value()
+            })
+            .collect::<Vec<Value>>(),
+    )
+}
+
+fn todos_to_value(todos: Vec<IcalTodo>, tag: Tag) -> UntaggedValue {
+    UntaggedValue::table(
+        &todos
+            .into_iter()
+            .map(|todo| {
+                let mut row = TaggedDictBuilder::new(tag.clone());
+                row.insert_untagged(
+                    "properties",
+                    properties_to_value(todo.properties, tag.clone()),
+                );
+                row.insert_untagged("alarms", alarms_to_value(todo.alarms, tag.clone()));
+                row.into_value()
+            })
+            .collect::<Vec<Value>>(),
+    )
+}
+
+fn journals_to_value(journals: Vec<IcalJournal>, tag: Tag) -> UntaggedValue {
+    UntaggedValue::table(
+        &journals
+            .into_iter()
+            .map(|journal| {
+                let mut row = TaggedDictBuilder::new(tag.clone());
+                row.insert_untagged(
+                    "properties",
+                    properties_to_value(journal.properties, tag.clone()),
+                );
+                row.into_value()
+            })
+            .collect::<Vec<Value>>(),
+    )
+}
+
+fn free_busys_to_value(free_busys: Vec<IcalFreeBusy>, tag: Tag) -> UntaggedValue {
+    UntaggedValue::table(
+        &free_busys
+            .into_iter()
+            .map(|free_busy| {
+                let mut row = TaggedDictBuilder::new(tag.clone());
+                row.insert_untagged(
+                    "properties",
+                    properties_to_value(free_busy.properties, tag.clone()),
+                );
+                row.into_value()
+            })
+            .collect::<Vec<Value>>(),
+    )
+}
+
+fn timezones_to_value(timezones: Vec<IcalTimeZone>, tag: Tag) -> UntaggedValue {
+    UntaggedValue::table(
+        &timezones
+            .into_iter()
+            .map(|timezone| {
+                let mut row = TaggedDictBuilder::new(tag.clone());
+                row.insert_untagged(
+                    "properties",
+                    properties_to_value(timezone.properties, tag.clone()),
+                );
+                row.insert_untagged(
+                    "transitions",
+                    timezone_transitions_to_value(timezone.transitions, tag.clone()),
+                );
+                row.into_value()
+            })
+            .collect::<Vec<Value>>(),
+    )
+}
+
+fn timezone_transitions_to_value(
+    transitions: Vec<IcalTimeZoneTransition>,
+    tag: Tag,
+) -> UntaggedValue {
+    UntaggedValue::table(
+        &transitions
+            .into_iter()
+            .map(|transition| {
+                let mut row = TaggedDictBuilder::new(tag.clone());
+                row.insert_untagged(
+                    "properties",
+                    properties_to_value(transition.properties, tag.clone()),
+                );
+                row.into_value()
+            })
+            .collect::<Vec<Value>>(),
+    )
+}
+
+fn properties_to_value(properties: Vec<Property>, tag: Tag) -> UntaggedValue {
+    UntaggedValue::table(
+        &properties
+            .into_iter()
+            .map(|prop| {
+                let mut row = TaggedDictBuilder::new(tag.clone());
+
+                let name = UntaggedValue::string(prop.name);
+                let value = match prop.value {
+                    Some(val) => UntaggedValue::string(val),
+                    None => UntaggedValue::Primitive(Primitive::Nothing),
+                };
+                let params = match prop.params {
+                    Some(param_list) => params_to_value(param_list, tag.clone()).into(),
+                    None => UntaggedValue::Primitive(Primitive::Nothing),
+                };
+
+                row.insert_untagged("name", name);
+                row.insert_untagged("value", value);
+                row.insert_untagged("params", params);
+                row.into_value()
+            })
+            .collect::<Vec<Value>>(),
+    )
+}
+
+fn params_to_value(params: Vec<(String, Vec<String>)>, tag: Tag) -> Value {
+    let mut row = TaggedDictBuilder::new(tag);
+
+    for (param_name, param_values) in params {
+        let values: Vec<Value> = param_values.into_iter().map(|val| val.into()).collect();
+        let values = UntaggedValue::table(&values);
+        row.insert_untagged(param_name, values);
+    }
+
+    row.into_value()
+}

crates/nu-cli/src/commands/from_ini.rs

@@ -1,6 +1,7 @@
 use crate::commands::WholeStreamCommand;
-use crate::data::{Primitive, TaggedDictBuilder, Value};
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue, Value};
 use std::collections::HashMap;
 
 pub struct FromINI;
@@ -27,40 +28,37 @@ impl WholeStreamCommand for FromINI {
     }
 }
 
-fn convert_ini_second_to_nu_value(
-    v: &HashMap<String, String>,
-    tag: impl Into<Tag>,
-) -> Tagged<Value> {
+fn convert_ini_second_to_nu_value(v: &HashMap<String, String>, tag: impl Into<Tag>) -> Value {
     let mut second = TaggedDictBuilder::new(tag);
 
-    for (key, value) in v.into_iter() {
-        second.insert(key.clone(), Primitive::String(value.clone()));
+    for (key, value) in v.iter() {
+        second.insert_untagged(key.clone(), Primitive::String(value.clone()));
     }
 
-    second.into_tagged_value()
+    second.into_value()
 }
 
 fn convert_ini_top_to_nu_value(
     v: &HashMap<String, HashMap<String, String>>,
     tag: impl Into<Tag>,
-) -> Tagged<Value> {
+) -> Value {
     let tag = tag.into();
     let mut top_level = TaggedDictBuilder::new(tag.clone());
 
     for (key, value) in v.iter() {
-        top_level.insert_tagged(
+        top_level.insert_value(
             key.clone(),
             convert_ini_second_to_nu_value(value, tag.clone()),
         );
     }
 
-    top_level.into_tagged_value()
+    top_level.into_value()
 }
 
 pub fn from_ini_string_to_value(
     s: String,
     tag: impl Into<Tag>,
-) -> Result<Tagged<Value>, serde_ini::de::Error> {
+) -> Result<Value, serde_ini::de::Error> {
     let v: HashMap<String, HashMap<String, String>> = serde_ini::from_str(&s)?;
     Ok(convert_ini_top_to_nu_value(&v, tag))
 }
@@ -71,48 +69,26 @@ fn from_ini(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStrea
     let input = args.input;
 
     let stream = async_stream! {
-        let values: Vec<Tagged<Value>> = input.values.collect().await;
+        let concat_string = input.collect_string(tag.clone()).await?;
 
-        let mut concat_string = String::new();
-        let mut latest_tag: Option<Tag> = None;
-
-        for value in values {
-            let value_tag = value.tag();
-            latest_tag = Some(value_tag.clone());
-            match value.item {
-                Value::Primitive(Primitive::String(s)) => {
-                    concat_string.push_str(&s);
-                    concat_string.push_str("\n");
-                }
-                _ => yield Err(ShellError::labeled_error_with_secondary(
-                    "Expected a string from pipeline",
-                    "requires string input",
-                    &tag,
-                    "value originates from here",
-                    &value_tag,
-                )),
-
-            }
-        }
-
-        match from_ini_string_to_value(concat_string, tag.clone()) {
+        match from_ini_string_to_value(concat_string.item, tag.clone()) {
             Ok(x) => match x {
-                Tagged { item: Value::Table(list), .. } => {
+                Value { value: UntaggedValue::Table(list), .. } => {
                     for l in list {
                         yield ReturnSuccess::value(l);
                     }
                 }
                 x => yield ReturnSuccess::value(x),
             },
-            Err(_) => if let Some(last_tag) = latest_tag {
+            Err(_) => {
                 yield Err(ShellError::labeled_error_with_secondary(
                     "Could not parse as INI",
                     "input cannot be parsed as INI",
                     &tag,
                     "value originates from here",
-                    last_tag,
+                    concat_string.tag,
                 ))
-            } ,
+            }
         }
     };
 

crates/nu-cli/src/commands/from_json.rs

@@ -0,0 +1,133 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue, Value};
+
+pub struct FromJSON;
+
+#[derive(Deserialize)]
+pub struct FromJSONArgs {
+    objects: bool,
+}
+
+impl WholeStreamCommand for FromJSON {
+    fn name(&self) -> &str {
+        "from-json"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("from-json").switch(
+            "objects",
+            "treat each line as a separate value",
+            Some('o'),
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Parse text as .json and create table."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, from_json)?.run()
+    }
+}
+
+fn convert_json_value_to_nu_value(v: &serde_hjson::Value, tag: impl Into<Tag>) -> Value {
+    let tag = tag.into();
+
+    match v {
+        serde_hjson::Value::Null => UntaggedValue::Primitive(Primitive::Nothing).into_value(&tag),
+        serde_hjson::Value::Bool(b) => UntaggedValue::boolean(*b).into_value(&tag),
+        serde_hjson::Value::F64(n) => UntaggedValue::decimal(*n).into_value(&tag),
+        serde_hjson::Value::U64(n) => UntaggedValue::int(*n).into_value(&tag),
+        serde_hjson::Value::I64(n) => UntaggedValue::int(*n).into_value(&tag),
+        serde_hjson::Value::String(s) => {
+            UntaggedValue::Primitive(Primitive::String(String::from(s))).into_value(&tag)
+        }
+        serde_hjson::Value::Array(a) => UntaggedValue::Table(
+            a.iter()
+                .map(|x| convert_json_value_to_nu_value(x, &tag))
+                .collect(),
+        )
+        .into_value(tag),
+        serde_hjson::Value::Object(o) => {
+            let mut collected = TaggedDictBuilder::new(&tag);
+            for (k, v) in o.iter() {
+                collected.insert_value(k.clone(), convert_json_value_to_nu_value(v, &tag));
+            }
+
+            collected.into_value()
+        }
+    }
+}
+
+pub fn from_json_string_to_value(s: String, tag: impl Into<Tag>) -> serde_hjson::Result<Value> {
+    let v: serde_hjson::Value = serde_hjson::from_str(&s)?;
+    Ok(convert_json_value_to_nu_value(&v, tag))
+}
+
+fn from_json(
+    FromJSONArgs { objects }: FromJSONArgs,
+    RunnableContext { input, name, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let name_tag = name;
+
+    let stream = async_stream! {
+        let concat_string = input.collect_string(name_tag.clone()).await?;
+
+        if objects {
+            for json_str in concat_string.item.lines() {
+                if json_str.is_empty() {
+                    continue;
+                }
+
+                match from_json_string_to_value(json_str.to_string(), &name_tag) {
+                    Ok(x) =>
+                        yield ReturnSuccess::value(x),
+                    Err(e) => {
+                        let mut message = "Could not parse as JSON (".to_string();
+                        message.push_str(&e.to_string());
+                        message.push_str(")");
+
+                        yield Err(ShellError::labeled_error_with_secondary(
+                            message,
+                            "input cannot be parsed as JSON",
+                            &name_tag,
+                            "value originates from here",
+                            concat_string.tag.clone()))
+                    }
+                }
+            }
+        } else {
+            match from_json_string_to_value(concat_string.item, name_tag.clone()) {
+                Ok(x) =>
+                    match x {
+                        Value { value: UntaggedValue::Table(list), .. } => {
+                            for l in list {
+                                yield ReturnSuccess::value(l);
+                            }
+                        }
+                        x => yield ReturnSuccess::value(x),
+                    }
+                Err(e) => {
+                    let mut message = "Could not parse as JSON (".to_string();
+                    message.push_str(&e.to_string());
+                    message.push_str(")");
+
+                    yield Err(ShellError::labeled_error_with_secondary(
+                        message,
+                        "input cannot be parsed as JSON",
+                        name_tag,
+                        "value originates from here",
+                        concat_string.tag))
+                }
+            }
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/from_ods.rs

@@ -0,0 +1,98 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use crate::TaggedListBuilder;
+use calamine::*;
+use nu_errors::ShellError;
+use nu_protocol::{ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue};
+use std::io::Cursor;
+
+pub struct FromODS;
+
+#[derive(Deserialize)]
+pub struct FromODSArgs {
+    headerless: bool,
+}
+
+impl WholeStreamCommand for FromODS {
+    fn name(&self) -> &str {
+        "from-ods"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("from-ods").switch(
+            "headerless",
+            "don't treat the first row as column names",
+            None,
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Parse OpenDocument Spreadsheet(.ods) data and create table."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, from_ods)?.run()
+    }
+}
+
+fn from_ods(
+    FromODSArgs {
+        headerless: _headerless,
+    }: FromODSArgs,
+    runnable_context: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let input = runnable_context.input;
+    let tag = runnable_context.name;
+
+    let stream = async_stream! {
+        let bytes = input.collect_binary(tag.clone()).await?;
+        let mut buf: Cursor<Vec<u8>> = Cursor::new(bytes.item);
+        let mut ods = Ods::<_>::new(buf).map_err(|_| ShellError::labeled_error(
+            "Could not load ods file",
+            "could not load ods file",
+            &tag))?;
+
+        let mut dict = TaggedDictBuilder::new(&tag);
+
+        let sheet_names = ods.sheet_names().to_owned();
+
+        for sheet_name in &sheet_names {
+            let mut sheet_output = TaggedListBuilder::new(&tag);
+
+            if let Some(Ok(current_sheet)) = ods.worksheet_range(sheet_name) {
+                for row in current_sheet.rows() {
+                    let mut row_output = TaggedDictBuilder::new(&tag);
+                    for (i, cell) in row.iter().enumerate() {
+                        let value = match cell {
+                            DataType::Empty => UntaggedValue::nothing(),
+                            DataType::String(s) => UntaggedValue::string(s),
+                            DataType::Float(f) => UntaggedValue::decimal(*f),
+                            DataType::Int(i) => UntaggedValue::int(*i),
+                            DataType::Bool(b) => UntaggedValue::boolean(*b),
+                            _ => UntaggedValue::nothing(),
+                        };
+
+                        row_output.insert_untagged(&format!("Column{}", i), value);
+                    }
+
+                    sheet_output.push_untagged(row_output.into_untagged_value());
+                }
+
+                dict.insert_untagged(sheet_name, sheet_output.into_untagged_value());
+            } else {
+                yield Err(ShellError::labeled_error(
+                    "Could not load sheet",
+                    "could not load sheet",
+                    &tag));
+            }
+        }
+
+        yield ReturnSuccess::value(dict.into_value());
+    };
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/from_sqlite.rs

@@ -1,7 +1,7 @@
 use crate::commands::WholeStreamCommand;
-use crate::data::{Primitive, TaggedDictBuilder, Value};
-use crate::errors::ShellError;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue, Value};
 use rusqlite::{types::ValueRef, Connection, Row, NO_PARAMS};
 use std::io::Write;
 use std::path::Path;
@@ -57,7 +57,7 @@ impl WholeStreamCommand for FromDB {
 pub fn convert_sqlite_file_to_nu_value(
     path: &Path,
     tag: impl Into<Tag> + Clone,
-) -> Result<Tagged<Value>, rusqlite::Error> {
+) -> Result<Value, rusqlite::Error> {
     let conn = Connection::open(path)?;
 
     let mut meta_out = Vec::new();
@@ -72,48 +72,54 @@ pub fn convert_sqlite_file_to_nu_value(
         while let Some(table_row) = table_rows.next()? {
             out.push(convert_sqlite_row_to_nu_value(table_row, tag.clone())?)
         }
-        meta_dict.insert_tagged(
+        meta_dict.insert_value(
             "table_name".to_string(),
-            Value::Primitive(Primitive::String(table_name)).tagged(tag.clone()),
+            UntaggedValue::Primitive(Primitive::String(table_name)).into_value(tag.clone()),
         );
-        meta_dict.insert_tagged("table_values", Value::Table(out).tagged(tag.clone()));
-        meta_out.push(meta_dict.into_tagged_value());
+        meta_dict.insert_value(
+            "table_values",
+            UntaggedValue::Table(out).into_value(tag.clone()),
+        );
+        meta_out.push(meta_dict.into_value());
     }
     let tag = tag.into();
-    Ok(Value::Table(meta_out).tagged(tag))
+    Ok(UntaggedValue::Table(meta_out).into_value(tag))
 }
 
 fn convert_sqlite_row_to_nu_value(
     row: &Row,
     tag: impl Into<Tag> + Clone,
-) -> Result<Tagged<Value>, rusqlite::Error> {
+) -> Result<Value, rusqlite::Error> {
     let mut collected = TaggedDictBuilder::new(tag.clone());
     for (i, c) in row.columns().iter().enumerate() {
-        collected.insert_tagged(
+        collected.insert_value(
             c.name().to_string(),
             convert_sqlite_value_to_nu_value(row.get_raw(i), tag.clone()),
         );
     }
-    return Ok(collected.into_tagged_value());
+    Ok(collected.into_value())
 }
 
-fn convert_sqlite_value_to_nu_value(value: ValueRef, tag: impl Into<Tag> + Clone) -> Tagged<Value> {
+fn convert_sqlite_value_to_nu_value(value: ValueRef, tag: impl Into<Tag> + Clone) -> Value {
     match value {
-        ValueRef::Null => Value::Primitive(Primitive::String(String::from(""))).tagged(tag),
-        ValueRef::Integer(i) => Value::number(i).tagged(tag),
-        ValueRef::Real(f) => Value::number(f).tagged(tag),
-        t @ ValueRef::Text(_) => {
-            // this unwrap is safe because we know the ValueRef is Text.
-            Value::Primitive(Primitive::String(t.as_str().unwrap().to_string())).tagged(tag)
+        ValueRef::Null => {
+            UntaggedValue::Primitive(Primitive::String(String::from(""))).into_value(tag)
         }
-        ValueRef::Blob(u) => Value::binary(u.to_owned()).tagged(tag),
+        ValueRef::Integer(i) => UntaggedValue::int(i).into_value(tag),
+        ValueRef::Real(f) => UntaggedValue::decimal(f).into_value(tag),
+        ValueRef::Text(s) => {
+            // this unwrap is safe because we know the ValueRef is Text.
+            UntaggedValue::Primitive(Primitive::String(String::from_utf8_lossy(s).to_string()))
+                .into_value(tag)
+        }
+        ValueRef::Blob(u) => UntaggedValue::binary(u.to_owned()).into_value(tag),
     }
 }
 
 pub fn from_sqlite_bytes_to_value(
     mut bytes: Vec<u8>,
     tag: impl Into<Tag> + Clone,
-) -> Result<Tagged<Value>, std::io::Error> {
+) -> Result<Value, std::io::Error> {
     // FIXME: should probably write a sqlite virtual filesystem
     // that will allow us to use bytes as a file to avoid this
     // write out, but this will require C code. Might be
@@ -132,39 +138,25 @@ fn from_sqlite(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputSt
     let input = args.input;
 
     let stream = async_stream! {
-        let values: Vec<Tagged<Value>> = input.values.collect().await;
-
-        for value in values {
-            let value_tag = value.tag();
-            match value.item {
-                Value::Primitive(Primitive::Binary(vb)) =>
-                    match from_sqlite_bytes_to_value(vb, tag.clone()) {
-                        Ok(x) => match x {
-                            Tagged { item: Value::Table(list), .. } => {
-                                for l in list {
-                                    yield ReturnSuccess::value(l);
-                                }
-                            }
-                            _ => yield ReturnSuccess::value(x),
-                        }
-                        Err(_) => {
-                            yield Err(ShellError::labeled_error_with_secondary(
-                                "Could not parse as SQLite",
-                                "input cannot be parsed as SQLite",
-                                &tag,
-                                "value originates from here",
-                                value_tag,
-                            ))
-                        }
+        let bytes = input.collect_binary(tag.clone()).await?;
+        match from_sqlite_bytes_to_value(bytes.item, tag.clone()) {
+            Ok(x) => match x {
+                Value { value: UntaggedValue::Table(list), .. } => {
+                    for l in list {
+                        yield ReturnSuccess::value(l);
                     }
-                _ => yield Err(ShellError::labeled_error_with_secondary(
-                    "Expected a string from pipeline",
-                    "requires string input",
+                }
+                _ => yield ReturnSuccess::value(x),
+            }
+            Err(err) => {
+                println!("{:?}", err);
+                yield Err(ShellError::labeled_error_with_secondary(
+                    "Could not parse as SQLite",
+                    "input cannot be parsed as SQLite",
                     &tag,
                     "value originates from here",
-                    value_tag,
-                )),
-
+                    bytes.tag,
+                ))
             }
         }
     };

crates/nu-cli/src/commands/from_ssv.rs

@@ -0,0 +1,492 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{
+    Primitive, ReturnSuccess, Signature, SyntaxShape, TaggedDictBuilder, UntaggedValue, Value,
+};
+use nu_source::Tagged;
+
+pub struct FromSSV;
+
+#[derive(Deserialize)]
+pub struct FromSSVArgs {
+    headerless: bool,
+    #[serde(rename(deserialize = "aligned-columns"))]
+    aligned_columns: bool,
+    #[serde(rename(deserialize = "minimum-spaces"))]
+    minimum_spaces: Option<Tagged<usize>>,
+}
+
+const STRING_REPRESENTATION: &str = "from-ssv";
+const DEFAULT_MINIMUM_SPACES: usize = 2;
+
+impl WholeStreamCommand for FromSSV {
+    fn name(&self) -> &str {
+        STRING_REPRESENTATION
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build(STRING_REPRESENTATION)
+            .switch(
+                "headerless",
+                "don't treat the first row as column names",
+                None,
+            )
+            .switch("aligned-columns", "assume columns are aligned", Some('a'))
+            .named(
+                "minimum-spaces",
+                SyntaxShape::Int,
+                "the minimum spaces to separate columns",
+                Some('m'),
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "Parse text as space-separated values and create a table. The default minimum number of spaces counted as a separator is 2."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, from_ssv)?.run()
+    }
+}
+
+enum HeaderOptions<'a> {
+    WithHeaders(&'a str),
+    WithoutHeaders,
+}
+
+fn parse_aligned_columns<'a>(
+    lines: impl Iterator<Item = &'a str>,
+    headers: HeaderOptions,
+    separator: &str,
+) -> Vec<Vec<(String, String)>> {
+    fn construct<'a>(
+        lines: impl Iterator<Item = &'a str>,
+        headers: Vec<(String, usize)>,
+    ) -> Vec<Vec<(String, String)>> {
+        lines
+            .map(|l| {
+                headers
+                    .iter()
+                    .enumerate()
+                    .map(|(i, (header_name, start_position))| {
+                        let val = match headers.get(i + 1) {
+                            Some((_, end)) => {
+                                if *end < l.len() {
+                                    l.get(*start_position..*end)
+                                } else {
+                                    l.get(*start_position..)
+                                }
+                            }
+                            None => l.get(*start_position..),
+                        }
+                        .unwrap_or("")
+                        .trim()
+                        .into();
+                        (header_name.clone(), val)
+                    })
+                    .collect()
+            })
+            .collect()
+    }
+
+    let find_indices = |line: &str| {
+        let values = line
+            .split(&separator)
+            .map(str::trim)
+            .filter(|s| !s.is_empty());
+        values
+            .fold(
+                (0, vec![]),
+                |(current_pos, mut indices), value| match line[current_pos..].find(value) {
+                    None => (current_pos, indices),
+                    Some(index) => {
+                        let absolute_index = current_pos + index;
+                        indices.push(absolute_index);
+                        (absolute_index + value.len(), indices)
+                    }
+                },
+            )
+            .1
+    };
+
+    let parse_with_headers = |lines, headers_raw: &str| {
+        let indices = find_indices(headers_raw);
+        let headers = headers_raw
+            .split(&separator)
+            .map(str::trim)
+            .filter(|s| !s.is_empty())
+            .map(String::from)
+            .zip(indices);
+
+        let columns = headers.collect::<Vec<(String, usize)>>();
+
+        construct(lines, columns)
+    };
+
+    let parse_without_headers = |ls: Vec<&str>| {
+        let mut indices = ls
+            .iter()
+            .flat_map(|s| find_indices(*s))
+            .collect::<Vec<usize>>();
+
+        indices.sort();
+        indices.dedup();
+
+        let headers: Vec<(String, usize)> = indices
+            .iter()
+            .enumerate()
+            .map(|(i, position)| (format!("Column{}", i + 1), *position))
+            .collect();
+
+        construct(ls.iter().map(|s| s.to_owned()), headers)
+    };
+
+    match headers {
+        HeaderOptions::WithHeaders(headers_raw) => parse_with_headers(lines, headers_raw),
+        HeaderOptions::WithoutHeaders => parse_without_headers(lines.collect()),
+    }
+}
+
+fn parse_separated_columns<'a>(
+    lines: impl Iterator<Item = &'a str>,
+    headers: HeaderOptions,
+    separator: &str,
+) -> Vec<Vec<(String, String)>> {
+    fn collect<'a>(
+        headers: Vec<String>,
+        rows: impl Iterator<Item = &'a str>,
+        separator: &str,
+    ) -> Vec<Vec<(String, String)>> {
+        rows.map(|r| {
+            headers
+                .iter()
+                .zip(r.split(separator).map(str::trim).filter(|s| !s.is_empty()))
+                .map(|(a, b)| (a.to_owned(), b.to_owned()))
+                .collect()
+        })
+        .collect()
+    }
+
+    let parse_with_headers = |lines, headers_raw: &str| {
+        let headers = headers_raw
+            .split(&separator)
+            .map(str::trim)
+            .map(str::to_owned)
+            .filter(|s| !s.is_empty())
+            .collect();
+        collect(headers, lines, separator)
+    };
+
+    let parse_without_headers = |ls: Vec<&str>| {
+        let num_columns = ls.iter().map(|r| r.len()).max().unwrap_or(0);
+
+        let headers = (1..=num_columns)
+            .map(|i| format!("Column{}", i))
+            .collect::<Vec<String>>();
+        collect(headers, ls.into_iter(), separator)
+    };
+
+    match headers {
+        HeaderOptions::WithHeaders(headers_raw) => parse_with_headers(lines, headers_raw),
+        HeaderOptions::WithoutHeaders => parse_without_headers(lines.collect()),
+    }
+}
+
+fn string_to_table(
+    s: &str,
+    headerless: bool,
+    aligned_columns: bool,
+    split_at: usize,
+) -> Vec<Vec<(String, String)>> {
+    let mut lines = s.lines().filter(|l| !l.trim().is_empty());
+    let separator = " ".repeat(std::cmp::max(split_at, 1));
+
+    let (ls, header_options) = if headerless {
+        (lines, HeaderOptions::WithoutHeaders)
+    } else {
+        match lines.next() {
+            Some(header) => (lines, HeaderOptions::WithHeaders(header)),
+            None => return vec![],
+        }
+    };
+
+    let f = if aligned_columns {
+        parse_aligned_columns
+    } else {
+        parse_separated_columns
+    };
+
+    f(ls, header_options, &separator)
+}
+
+fn from_ssv_string_to_value(
+    s: &str,
+    headerless: bool,
+    aligned_columns: bool,
+    split_at: usize,
+    tag: impl Into<Tag>,
+) -> Option<Value> {
+    let tag = tag.into();
+    let rows = string_to_table(s, headerless, aligned_columns, split_at)
+        .iter()
+        .map(|row| {
+            let mut tagged_dict = TaggedDictBuilder::new(&tag);
+            for (col, entry) in row {
+                tagged_dict.insert_value(
+                    col,
+                    UntaggedValue::Primitive(Primitive::String(String::from(entry)))
+                        .into_value(&tag),
+                )
+            }
+            tagged_dict.into_value()
+        })
+        .collect();
+
+    Some(UntaggedValue::Table(rows).into_value(&tag))
+}
+
+fn from_ssv(
+    FromSSVArgs {
+        headerless,
+        aligned_columns,
+        minimum_spaces,
+    }: FromSSVArgs,
+    RunnableContext { input, name, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let stream = async_stream! {
+        let concat_string = input.collect_string(name.clone()).await?;
+        let split_at = match minimum_spaces {
+            Some(number) => number.item,
+            None => DEFAULT_MINIMUM_SPACES
+        };
+
+        match from_ssv_string_to_value(&concat_string.item, headerless, aligned_columns, split_at, name.clone()) {
+            Some(x) => match x {
+                Value { value: UntaggedValue::Table(list), ..} => {
+                    for l in list { yield ReturnSuccess::value(l) }
+                }
+                x => yield ReturnSuccess::value(x)
+            },
+            None => {
+                yield Err(ShellError::labeled_error_with_secondary(
+                    "Could not parse as SSV",
+                    "input cannot be parsed ssv",
+                    &name,
+                    "value originates from here",
+                    &concat_string.tag,
+                ))
+            },
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    fn owned(x: &str, y: &str) -> (String, String) {
+        (String::from(x), String::from(y))
+    }
+
+    #[test]
+    fn it_trims_empty_and_whitespace_only_lines() {
+        let input = r#"
+
+            a       b
+
+            1       2
+
+            3       4
+        "#;
+        let result = string_to_table(input, false, true, 1);
+        assert_eq!(
+            result,
+            vec![
+                vec![owned("a", "1"), owned("b", "2")],
+                vec![owned("a", "3"), owned("b", "4")]
+            ]
+        );
+    }
+
+    #[test]
+    fn it_deals_with_single_column_input() {
+        let input = r#"
+            a
+            1
+            2
+        "#;
+        let result = string_to_table(input, false, true, 1);
+        assert_eq!(result, vec![vec![owned("a", "1")], vec![owned("a", "2")]]);
+    }
+
+    #[test]
+    fn it_uses_first_row_as_data_when_headerless() {
+        let input = r#"
+            a b
+            1 2
+            3 4
+        "#;
+        let result = string_to_table(input, true, true, 1);
+        assert_eq!(
+            result,
+            vec![
+                vec![owned("Column1", "a"), owned("Column2", "b")],
+                vec![owned("Column1", "1"), owned("Column2", "2")],
+                vec![owned("Column1", "3"), owned("Column2", "4")]
+            ]
+        );
+    }
+
+    #[test]
+    fn it_allows_a_predefined_number_of_spaces() {
+        let input = r#"
+            column a   column b
+            entry 1    entry number  2
+            3          four
+        "#;
+
+        let result = string_to_table(input, false, true, 3);
+        assert_eq!(
+            result,
+            vec![
+                vec![
+                    owned("column a", "entry 1"),
+                    owned("column b", "entry number  2")
+                ],
+                vec![owned("column a", "3"), owned("column b", "four")]
+            ]
+        );
+    }
+
+    #[test]
+    fn it_trims_remaining_separator_space() {
+        let input = r#"
+            colA   colB     colC
+            val1   val2     val3
+        "#;
+
+        let trimmed = |s: &str| s.trim() == s;
+
+        let result = string_to_table(input, false, true, 2);
+        assert!(result
+            .iter()
+            .all(|row| row.iter().all(|(a, b)| trimmed(a) && trimmed(b))));
+    }
+
+    #[test]
+    fn it_keeps_empty_columns() {
+        let input = r#"
+            colA   col B     col C
+                   val2      val3
+            val4   val 5     val 6
+            val7             val8
+        "#;
+
+        let result = string_to_table(input, false, true, 2);
+        assert_eq!(
+            result,
+            vec![
+                vec![
+                    owned("colA", ""),
+                    owned("col B", "val2"),
+                    owned("col C", "val3")
+                ],
+                vec![
+                    owned("colA", "val4"),
+                    owned("col B", "val 5"),
+                    owned("col C", "val 6")
+                ],
+                vec![
+                    owned("colA", "val7"),
+                    owned("col B", ""),
+                    owned("col C", "val8")
+                ],
+            ]
+        );
+    }
+
+    #[test]
+    fn it_can_produce_an_empty_stream_for_header_only_input() {
+        let input = "colA   col B";
+
+        let result = string_to_table(input, false, true, 2);
+        let expected: Vec<Vec<(String, String)>> = vec![];
+        assert_eq!(expected, result);
+    }
+
+    #[test]
+    fn it_uses_the_full_final_column() {
+        let input = r#"
+            colA   col B
+            val1   val2   trailing value that should be included
+        "#;
+
+        let result = string_to_table(input, false, true, 2);
+        assert_eq!(
+            result,
+            vec![vec![
+                owned("colA", "val1"),
+                owned("col B", "val2   trailing value that should be included"),
+            ]]
+        );
+    }
+
+    #[test]
+    fn it_handles_empty_values_when_headerless_and_aligned_columns() {
+        let input = r#"
+            a multi-word value  b           d
+            1                        3-3    4
+                                                       last
+        "#;
+
+        let result = string_to_table(input, true, true, 2);
+        assert_eq!(
+            result,
+            vec![
+                vec![
+                    owned("Column1", "a multi-word value"),
+                    owned("Column2", "b"),
+                    owned("Column3", ""),
+                    owned("Column4", "d"),
+                    owned("Column5", "")
+                ],
+                vec![
+                    owned("Column1", "1"),
+                    owned("Column2", ""),
+                    owned("Column3", "3-3"),
+                    owned("Column4", "4"),
+                    owned("Column5", "")
+                ],
+                vec![
+                    owned("Column1", ""),
+                    owned("Column2", ""),
+                    owned("Column3", ""),
+                    owned("Column4", ""),
+                    owned("Column5", "last")
+                ],
+            ]
+        );
+    }
+
+    #[test]
+    fn input_is_parsed_correctly_if_either_option_works() {
+        let input = r#"
+                docker-registry   docker-registry=default                   docker-registry=default   172.30.78.158   5000/TCP
+                kubernetes        component=apiserver,provider=kubernetes   <none>                    172.30.0.2      443/TCP
+                kubernetes-ro     component=apiserver,provider=kubernetes   <none>                    172.30.0.1      80/TCP
+            "#;
+
+        let aligned_columns_headerless = string_to_table(input, true, true, 2);
+        let separator_headerless = string_to_table(input, true, false, 2);
+        let aligned_columns_with_headers = string_to_table(input, false, true, 2);
+        let separator_with_headers = string_to_table(input, false, false, 2);
+        assert_eq!(aligned_columns_headerless, separator_headerless);
+        assert_eq!(aligned_columns_with_headers, separator_with_headers);
+    }
+}

crates/nu-cli/src/commands/from_toml.rs

@@ -1,6 +1,7 @@
 use crate::commands::WholeStreamCommand;
-use crate::data::{Primitive, TaggedDictBuilder, Value};
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue, Value};
 
 pub struct FromTOML;
 
@@ -26,39 +27,38 @@ impl WholeStreamCommand for FromTOML {
     }
 }
 
-pub fn convert_toml_value_to_nu_value(v: &toml::Value, tag: impl Into<Tag>) -> Tagged<Value> {
+pub fn convert_toml_value_to_nu_value(v: &toml::Value, tag: impl Into<Tag>) -> Value {
     let tag = tag.into();
 
     match v {
-        toml::Value::Boolean(b) => Value::boolean(*b).tagged(tag),
-        toml::Value::Integer(n) => Value::number(n).tagged(tag),
-        toml::Value::Float(n) => Value::number(n).tagged(tag),
-        toml::Value::String(s) => Value::Primitive(Primitive::String(String::from(s))).tagged(tag),
-        toml::Value::Array(a) => Value::Table(
+        toml::Value::Boolean(b) => UntaggedValue::boolean(*b).into_value(tag),
+        toml::Value::Integer(n) => UntaggedValue::int(*n).into_value(tag),
+        toml::Value::Float(n) => UntaggedValue::decimal(*n).into_value(tag),
+        toml::Value::String(s) => {
+            UntaggedValue::Primitive(Primitive::String(String::from(s))).into_value(tag)
+        }
+        toml::Value::Array(a) => UntaggedValue::Table(
             a.iter()
                 .map(|x| convert_toml_value_to_nu_value(x, &tag))
                 .collect(),
         )
-        .tagged(tag),
+        .into_value(tag),
         toml::Value::Datetime(dt) => {
-            Value::Primitive(Primitive::String(dt.to_string())).tagged(tag)
+            UntaggedValue::Primitive(Primitive::String(dt.to_string())).into_value(tag)
         }
         toml::Value::Table(t) => {
             let mut collected = TaggedDictBuilder::new(&tag);
 
             for (k, v) in t.iter() {
-                collected.insert_tagged(k.clone(), convert_toml_value_to_nu_value(v, &tag));
+                collected.insert_value(k.clone(), convert_toml_value_to_nu_value(v, &tag));
             }
 
-            collected.into_tagged_value()
+            collected.into_value()
         }
     }
 }
 
-pub fn from_toml_string_to_value(
-    s: String,
-    tag: impl Into<Tag>,
-) -> Result<Tagged<Value>, toml::de::Error> {
+pub fn from_toml_string_to_value(s: String, tag: impl Into<Tag>) -> Result<Value, toml::de::Error> {
     let v: toml::Value = s.parse::<toml::Value>()?;
     Ok(convert_toml_value_to_nu_value(&v, tag))
 }
@@ -72,48 +72,25 @@ pub fn from_toml(
     let input = args.input;
 
     let stream = async_stream! {
-        let values: Vec<Tagged<Value>> = input.values.collect().await;
-
-        let mut concat_string = String::new();
-        let mut latest_tag: Option<Tag> = None;
-
-        for value in values {
-            let value_tag = value.tag();
-            latest_tag = Some(value_tag.clone());
-            match value.item {
-                Value::Primitive(Primitive::String(s)) => {
-                    concat_string.push_str(&s);
-                    concat_string.push_str("\n");
-                }
-                _ => yield Err(ShellError::labeled_error_with_secondary(
-                    "Expected a string from pipeline",
-                    "requires string input",
-                    &tag,
-                    "value originates from here",
-                    &value_tag,
-                )),
-
-            }
-        }
-
-        match from_toml_string_to_value(concat_string, tag.clone()) {
+        let concat_string = input.collect_string(tag.clone()).await?;
+        match from_toml_string_to_value(concat_string.item, tag.clone()) {
             Ok(x) => match x {
-                Tagged { item: Value::Table(list), .. } => {
+                Value { value: UntaggedValue::Table(list), .. } => {
                     for l in list {
                         yield ReturnSuccess::value(l);
                     }
                 }
                 x => yield ReturnSuccess::value(x),
             },
-            Err(_) => if let Some(last_tag) = latest_tag {
+            Err(_) => {
                 yield Err(ShellError::labeled_error_with_secondary(
                     "Could not parse as TOML",
                     "input cannot be parsed as TOML",
                     &tag,
                     "value originates from here",
-                    last_tag,
+                    concat_string.tag,
                 ))
-            } ,
+            }
         }
     };
 

crates/nu-cli/src/commands/from_tsv.rs

@@ -0,0 +1,45 @@
+use crate::commands::from_delimited_data::from_delimited_data;
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::Signature;
+
+pub struct FromTSV;
+
+#[derive(Deserialize)]
+pub struct FromTSVArgs {
+    headerless: bool,
+}
+
+impl WholeStreamCommand for FromTSV {
+    fn name(&self) -> &str {
+        "from-tsv"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("from-tsv").switch(
+            "headerless",
+            "don't treat the first row as column names",
+            None,
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Parse text as .tsv and create table."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, from_tsv)?.run()
+    }
+}
+
+fn from_tsv(
+    FromTSVArgs { headerless }: FromTSVArgs,
+    runnable_context: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    from_delimited_data(headerless, '\t', "TSV", runnable_context)
+}

crates/nu-cli/src/commands/from_url.rs

@@ -0,0 +1,63 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue};
+
+pub struct FromURL;
+
+impl WholeStreamCommand for FromURL {
+    fn name(&self) -> &str {
+        "from-url"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("from-url")
+    }
+
+    fn usage(&self) -> &str {
+        "Parse url-encoded string as a table."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        from_url(args, registry)
+    }
+}
+
+fn from_url(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStream, ShellError> {
+    let args = args.evaluate_once(registry)?;
+    let tag = args.name_tag();
+    let input = args.input;
+
+    let stream = async_stream! {
+        let concat_string = input.collect_string(tag.clone()).await?;
+
+        let result = serde_urlencoded::from_str::<Vec<(String, String)>>(&concat_string.item);
+
+        match result {
+            Ok(result) => {
+                let mut row = TaggedDictBuilder::new(tag);
+
+                for (k,v) in result {
+                    row.insert_untagged(k, UntaggedValue::string(v));
+                }
+
+                yield ReturnSuccess::value(row.into_value());
+            }
+            _ => {
+                yield Err(ShellError::labeled_error_with_secondary(
+                    "String not compatible with url-encoding",
+                    "input not url-encoded",
+                    tag,
+                    "value originates from here",
+                    concat_string.tag,
+                ));
+            }
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/from_vcf.rs

@@ -0,0 +1,102 @@
+extern crate ical;
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use ical::parser::vcard::component::*;
+use ical::property::Property;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue, Value};
+use std::io::BufReader;
+
+pub struct FromVcf;
+
+impl WholeStreamCommand for FromVcf {
+    fn name(&self) -> &str {
+        "from-vcf"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("from-vcf")
+    }
+
+    fn usage(&self) -> &str {
+        "Parse text as .vcf and create table."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        from_vcf(args, registry)
+    }
+}
+
+fn from_vcf(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStream, ShellError> {
+    let args = args.evaluate_once(registry)?;
+    let tag = args.name_tag();
+    let input = args.input;
+
+    let stream = async_stream! {
+        let input_string = input.collect_string(tag.clone()).await?.item;
+        let input_bytes = input_string.as_bytes();
+        let buf_reader = BufReader::new(input_bytes);
+        let parser = ical::VcardParser::new(buf_reader);
+
+        for contact in parser {
+            match contact {
+                Ok(c) => yield ReturnSuccess::value(contact_to_value(c, tag.clone())),
+                Err(_) => yield Err(ShellError::labeled_error(
+                    "Could not parse as .vcf",
+                    "input cannot be parsed as .vcf",
+                    tag.clone()
+                )),
+            }
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}
+
+fn contact_to_value(contact: VcardContact, tag: Tag) -> Value {
+    let mut row = TaggedDictBuilder::new(tag.clone());
+    row.insert_untagged("properties", properties_to_value(contact.properties, tag));
+    row.into_value()
+}
+
+fn properties_to_value(properties: Vec<Property>, tag: Tag) -> UntaggedValue {
+    UntaggedValue::table(
+        &properties
+            .into_iter()
+            .map(|prop| {
+                let mut row = TaggedDictBuilder::new(tag.clone());
+
+                let name = UntaggedValue::string(prop.name);
+                let value = match prop.value {
+                    Some(val) => UntaggedValue::string(val),
+                    None => UntaggedValue::Primitive(Primitive::Nothing),
+                };
+                let params = match prop.params {
+                    Some(param_list) => params_to_value(param_list, tag.clone()).into(),
+                    None => UntaggedValue::Primitive(Primitive::Nothing),
+                };
+
+                row.insert_untagged("name", name);
+                row.insert_untagged("value", value);
+                row.insert_untagged("params", params);
+                row.into_value()
+            })
+            .collect::<Vec<Value>>(),
+    )
+}
+
+fn params_to_value(params: Vec<(String, Vec<String>)>, tag: Tag) -> Value {
+    let mut row = TaggedDictBuilder::new(tag);
+
+    for (param_name, param_values) in params {
+        let values: Vec<Value> = param_values.into_iter().map(|val| val.into()).collect();
+        let values = UntaggedValue::table(&values);
+        row.insert_untagged(param_name, values);
+    }
+
+    row.into_value()
+}

crates/nu-cli/src/commands/from_xlsx.rs

@@ -0,0 +1,99 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use crate::TaggedListBuilder;
+use calamine::*;
+use nu_errors::ShellError;
+use nu_protocol::{ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue};
+use std::io::Cursor;
+
+pub struct FromXLSX;
+
+#[derive(Deserialize)]
+pub struct FromXLSXArgs {
+    headerless: bool,
+}
+
+impl WholeStreamCommand for FromXLSX {
+    fn name(&self) -> &str {
+        "from-xlsx"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("from-xlsx").switch(
+            "headerless",
+            "don't treat the first row as column names",
+            None,
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Parse binary Excel(.xlsx) data and create table."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, from_xlsx)?.run()
+    }
+}
+
+fn from_xlsx(
+    FromXLSXArgs {
+        headerless: _headerless,
+    }: FromXLSXArgs,
+    runnable_context: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let input = runnable_context.input;
+    let tag = runnable_context.name;
+
+    let stream = async_stream! {
+        let value = input.collect_binary(tag.clone()).await?;
+
+        let mut buf: Cursor<Vec<u8>> = Cursor::new(value.item);
+        let mut xls = Xlsx::<_>::new(buf).map_err(|_| {
+            ShellError::labeled_error("Could not load xlsx file", "could not load xlsx file", &tag)
+        })?;
+
+        let mut dict = TaggedDictBuilder::new(&tag);
+
+        let sheet_names = xls.sheet_names().to_owned();
+
+        for sheet_name in &sheet_names {
+            let mut sheet_output = TaggedListBuilder::new(&tag);
+
+            if let Some(Ok(current_sheet)) = xls.worksheet_range(sheet_name) {
+                for row in current_sheet.rows() {
+                    let mut row_output = TaggedDictBuilder::new(&tag);
+                    for (i, cell) in row.iter().enumerate() {
+                        let value = match cell {
+                            DataType::Empty => UntaggedValue::nothing(),
+                            DataType::String(s) => UntaggedValue::string(s),
+                            DataType::Float(f) => UntaggedValue::decimal(*f),
+                            DataType::Int(i) => UntaggedValue::int(*i),
+                            DataType::Bool(b) => UntaggedValue::boolean(*b),
+                            _ => UntaggedValue::nothing(),
+                        };
+
+                        row_output.insert_untagged(&format!("Column{}", i), value);
+                    }
+
+                    sheet_output.push_untagged(row_output.into_untagged_value());
+                }
+
+                dict.insert_untagged(sheet_name, sheet_output.into_untagged_value());
+            } else {
+                yield Err(ShellError::labeled_error(
+                    "Could not load sheet",
+                    "could not load sheet",
+                    &tag,
+                ));
+            }
+        }
+
+        yield ReturnSuccess::value(dict.into_value());
+    };
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/from_xml.rs

@@ -0,0 +1,303 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue, Value};
+
+pub struct FromXML;
+
+impl WholeStreamCommand for FromXML {
+    fn name(&self) -> &str {
+        "from-xml"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("from-xml")
+    }
+
+    fn usage(&self) -> &str {
+        "Parse text as .xml and create table."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        from_xml(args, registry)
+    }
+}
+
+fn from_attributes_to_value(attributes: &[roxmltree::Attribute], tag: impl Into<Tag>) -> Value {
+    let tag = tag.into();
+
+    let mut collected = TaggedDictBuilder::new(tag);
+    for a in attributes {
+        collected.insert_untagged(String::from(a.name()), UntaggedValue::string(a.value()));
+    }
+
+    collected.into_value()
+}
+
+fn from_node_to_value<'a, 'd>(n: &roxmltree::Node<'a, 'd>, tag: impl Into<Tag>) -> Value {
+    let tag = tag.into();
+
+    if n.is_element() {
+        let name = n.tag_name().name().trim().to_string();
+
+        let mut children_values = vec![];
+        for c in n.children() {
+            children_values.push(from_node_to_value(&c, &tag));
+        }
+
+        let children_values: Vec<Value> = children_values
+            .into_iter()
+            .filter(|x| match x {
+                Value {
+                    value: UntaggedValue::Primitive(Primitive::String(f)),
+                    ..
+                } => {
+                    !f.trim().is_empty() // non-whitespace characters?
+                }
+                _ => true,
+            })
+            .collect();
+
+        let mut collected = TaggedDictBuilder::new(&tag);
+
+        let attribute_value: Value = from_attributes_to_value(&n.attributes(), &tag);
+
+        let mut row = TaggedDictBuilder::new(&tag);
+        row.insert_untagged(
+            String::from("children"),
+            UntaggedValue::Table(children_values),
+        );
+        row.insert_untagged(String::from("attributes"), attribute_value);
+        collected.insert_untagged(name, row.into_value());
+
+        collected.into_value()
+    } else if n.is_comment() {
+        UntaggedValue::string("<comment>").into_value(tag)
+    } else if n.is_pi() {
+        UntaggedValue::string("<processing_instruction>").into_value(tag)
+    } else if n.is_text() {
+        match n.text() {
+            Some(text) => UntaggedValue::string(text).into_value(tag),
+            None => UntaggedValue::string("<error>").into_value(tag),
+        }
+    } else {
+        UntaggedValue::string("<unknown>").into_value(tag)
+    }
+}
+
+fn from_document_to_value(d: &roxmltree::Document, tag: impl Into<Tag>) -> Value {
+    from_node_to_value(&d.root_element(), tag)
+}
+
+pub fn from_xml_string_to_value(s: String, tag: impl Into<Tag>) -> Result<Value, roxmltree::Error> {
+    let parsed = roxmltree::Document::parse(&s)?;
+    Ok(from_document_to_value(&parsed, tag))
+}
+
+fn from_xml(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStream, ShellError> {
+    let args = args.evaluate_once(registry)?;
+    let tag = args.name_tag();
+    let input = args.input;
+
+    let stream = async_stream! {
+        let concat_string = input.collect_string(tag.clone()).await?;
+
+        match from_xml_string_to_value(concat_string.item, tag.clone()) {
+            Ok(x) => match x {
+                Value { value: UntaggedValue::Table(list), .. } => {
+                    for l in list {
+                        yield ReturnSuccess::value(l);
+                    }
+                }
+                x => yield ReturnSuccess::value(x),
+            },
+            Err(_) => {
+                yield Err(ShellError::labeled_error_with_secondary(
+                    "Could not parse as XML",
+                    "input cannot be parsed as XML",
+                    &tag,
+                    "value originates from here",
+                    &concat_string.tag,
+                ))
+            } ,
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}
+
+#[cfg(test)]
+mod tests {
+
+    use crate::commands::from_xml;
+    use indexmap::IndexMap;
+    use nu_protocol::{UntaggedValue, Value};
+    use nu_source::*;
+
+    fn string(input: impl Into<String>) -> Value {
+        UntaggedValue::string(input.into()).into_untagged_value()
+    }
+
+    fn row(entries: IndexMap<String, Value>) -> Value {
+        UntaggedValue::row(entries).into_untagged_value()
+    }
+
+    fn table(list: &[Value]) -> Value {
+        UntaggedValue::table(list).into_untagged_value()
+    }
+
+    fn parse(xml: &str) -> Result<Value, roxmltree::Error> {
+        from_xml::from_xml_string_to_value(xml.to_string(), Tag::unknown())
+    }
+
+    #[test]
+    fn parses_empty_element() -> Result<(), roxmltree::Error> {
+        let source = "<nu></nu>";
+
+        assert_eq!(
+            parse(source)?,
+            row(indexmap! {
+                "nu".into() => row(indexmap! {
+                    "children".into() => table(&[]),
+                    "attributes".into() => row(indexmap! {})
+                })
+            })
+        );
+
+        Ok(())
+    }
+
+    #[test]
+    fn parses_element_with_text() -> Result<(), roxmltree::Error> {
+        let source = "<nu>La era de los tres caballeros</nu>";
+
+        assert_eq!(
+            parse(source)?,
+            row(indexmap! {
+                "nu".into() => row(indexmap! {
+                    "children".into() => table(&[string("La era de los tres caballeros")]),
+                    "attributes".into() => row(indexmap! {})
+                })
+            })
+        );
+
+        Ok(())
+    }
+
+    #[test]
+    fn parses_element_with_elements() -> Result<(), roxmltree::Error> {
+        let source = "\
+<nu>
+    <dev>Andrés</dev>
+    <dev>Jonathan</dev>
+    <dev>Yehuda</dev>
+</nu>";
+
+        assert_eq!(
+            parse(source)?,
+            row(indexmap! {
+                "nu".into() => row(indexmap! {
+                    "children".into() => table(&[
+                        row(indexmap! {
+                            "dev".into() => row(indexmap! {
+                                "children".into() => table(&[string("Andrés")]),
+                                "attributes".into() => row(indexmap! {})
+                            })
+                        }),
+                        row(indexmap! {
+                            "dev".into() => row(indexmap! {
+                                "children".into() => table(&[string("Jonathan")]),
+                                "attributes".into() => row(indexmap! {})
+                            })
+                        }),
+                        row(indexmap! {
+                            "dev".into() => row(indexmap! {
+                                "children".into() => table(&[string("Yehuda")]),
+                                "attributes".into() => row(indexmap! {})
+                            })
+                        })
+                    ]),
+                    "attributes".into() => row(indexmap! {})
+                })
+            })
+        );
+
+        Ok(())
+    }
+
+    #[test]
+    fn parses_element_with_attribute() -> Result<(), roxmltree::Error> {
+        let source = "\
+<nu version=\"2.0\">
+</nu>";
+
+        assert_eq!(
+            parse(source)?,
+            row(indexmap! {
+                "nu".into() => row(indexmap! {
+                    "children".into() => table(&[]),
+                    "attributes".into() => row(indexmap! {
+                        "version".into() => string("2.0")
+                    })
+                })
+            })
+        );
+
+        Ok(())
+    }
+
+    #[test]
+    fn parses_element_with_attribute_and_element() -> Result<(), roxmltree::Error> {
+        let source = "\
+<nu version=\"2.0\">
+    <version>2.0</version>
+</nu>";
+
+        assert_eq!(
+            parse(source)?,
+            row(indexmap! {
+                "nu".into() => row(indexmap! {
+                    "children".into() => table(&[
+                           row(indexmap! {
+                                "version".into() => row(indexmap! {
+                                    "children".into() => table(&[string("2.0")]),
+                                    "attributes".into() => row(indexmap! {})
+                                })
+                          })
+                    ]),
+                    "attributes".into() => row(indexmap! {
+                        "version".into() => string("2.0")
+                    })
+                })
+            })
+        );
+
+        Ok(())
+    }
+
+    #[test]
+    fn parses_element_with_multiple_attributes() -> Result<(), roxmltree::Error> {
+        let source = "\
+<nu version=\"2.0\" age=\"25\">
+</nu>";
+
+        assert_eq!(
+            parse(source)?,
+            row(indexmap! {
+                "nu".into() => row(indexmap! {
+                    "children".into() => table(&[]),
+                    "attributes".into() => row(indexmap! {
+                        "version".into() => string("2.0"),
+                        "age".into() => string("25")
+                    })
+                })
+            })
+        );
+
+        Ok(())
+    }
+}

crates/nu-cli/src/commands/from_yaml.rs

@@ -1,6 +1,7 @@
 use crate::commands::WholeStreamCommand;
-use crate::data::{Primitive, TaggedDictBuilder, Value};
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, TaggedDictBuilder, UntaggedValue, Value};
 
 pub struct FromYAML;
 
@@ -50,49 +51,71 @@ impl WholeStreamCommand for FromYML {
     }
 }
 
-fn convert_yaml_value_to_nu_value(v: &serde_yaml::Value, tag: impl Into<Tag>) -> Tagged<Value> {
+fn convert_yaml_value_to_nu_value(
+    v: &serde_yaml::Value,
+    tag: impl Into<Tag>,
+) -> Result<Value, ShellError> {
     let tag = tag.into();
 
-    match v {
-        serde_yaml::Value::Bool(b) => Value::boolean(*b).tagged(tag),
+    Ok(match v {
+        serde_yaml::Value::Bool(b) => UntaggedValue::boolean(*b).into_value(tag),
         serde_yaml::Value::Number(n) if n.is_i64() => {
-            Value::number(n.as_i64().unwrap()).tagged(tag)
+            UntaggedValue::int(n.as_i64().ok_or_else(|| {
+                ShellError::labeled_error(
+                    "Expected a compatible number",
+                    "expected a compatible number",
+                    &tag,
+                )
+            })?)
+            .into_value(tag)
         }
         serde_yaml::Value::Number(n) if n.is_f64() => {
-            Value::Primitive(Primitive::from(n.as_f64().unwrap())).tagged(tag)
+            UntaggedValue::decimal(n.as_f64().ok_or_else(|| {
+                ShellError::labeled_error(
+                    "Expected a compatible number",
+                    "expected a compatible number",
+                    &tag,
+                )
+            })?)
+            .into_value(tag)
         }
-        serde_yaml::Value::String(s) => Value::string(s).tagged(tag),
-        serde_yaml::Value::Sequence(a) => Value::Table(
-            a.iter()
+        serde_yaml::Value::String(s) => UntaggedValue::string(s).into_value(tag),
+        serde_yaml::Value::Sequence(a) => {
+            let result: Result<Vec<Value>, ShellError> = a
+                .iter()
                 .map(|x| convert_yaml_value_to_nu_value(x, &tag))
-                .collect(),
-        )
-        .tagged(tag),
+                .collect();
+            UntaggedValue::Table(result?).into_value(tag)
+        }
         serde_yaml::Value::Mapping(t) => {
             let mut collected = TaggedDictBuilder::new(&tag);
 
             for (k, v) in t.iter() {
                 match k {
                     serde_yaml::Value::String(k) => {
-                        collected.insert_tagged(k.clone(), convert_yaml_value_to_nu_value(v, &tag));
+                        collected.insert_value(k.clone(), convert_yaml_value_to_nu_value(v, &tag)?);
                     }
                     _ => unimplemented!("Unknown key type"),
                 }
             }
 
-            collected.into_tagged_value()
+            collected.into_value()
         }
-        serde_yaml::Value::Null => Value::Primitive(Primitive::Nothing).tagged(tag),
+        serde_yaml::Value::Null => UntaggedValue::Primitive(Primitive::Nothing).into_value(tag),
         x => unimplemented!("Unsupported yaml case: {:?}", x),
-    }
+    })
 }
 
-pub fn from_yaml_string_to_value(
-    s: String,
-    tag: impl Into<Tag>,
-) -> serde_yaml::Result<Tagged<Value>> {
-    let v: serde_yaml::Value = serde_yaml::from_str(&s)?;
-    Ok(convert_yaml_value_to_nu_value(&v, tag))
+pub fn from_yaml_string_to_value(s: String, tag: impl Into<Tag>) -> Result<Value, ShellError> {
+    let tag = tag.into();
+    let v: serde_yaml::Value = serde_yaml::from_str(&s).map_err(|x| {
+        ShellError::labeled_error(
+            format!("Could not load yaml: {}", x),
+            "could not load yaml from text",
+            &tag,
+        )
+    })?;
+    Ok(convert_yaml_value_to_nu_value(&v, tag)?)
 }
 
 fn from_yaml(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStream, ShellError> {
@@ -101,48 +124,26 @@ fn from_yaml(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStre
     let input = args.input;
 
     let stream = async_stream! {
-        let values: Vec<Tagged<Value>> = input.values.collect().await;
+        let concat_string = input.collect_string(tag.clone()).await?;
 
-        let mut concat_string = String::new();
-        let mut latest_tag: Option<Tag> = None;
-
-        for value in values {
-            let value_tag = value.tag();
-            latest_tag = Some(value_tag.clone());
-            match value.item {
-                Value::Primitive(Primitive::String(s)) => {
-                    concat_string.push_str(&s);
-                    concat_string.push_str("\n");
-                }
-                _ => yield Err(ShellError::labeled_error_with_secondary(
-                    "Expected a string from pipeline",
-                    "requires string input",
-                    &tag,
-                    "value originates from here",
-                    &value_tag,
-                )),
-
-            }
-        }
-
-        match from_yaml_string_to_value(concat_string, tag.clone()) {
+        match from_yaml_string_to_value(concat_string.item, tag.clone()) {
             Ok(x) => match x {
-                Tagged { item: Value::Table(list), .. } => {
+                Value { value: UntaggedValue::Table(list), .. } => {
                     for l in list {
                         yield ReturnSuccess::value(l);
                     }
                 }
                 x => yield ReturnSuccess::value(x),
             },
-            Err(_) => if let Some(last_tag) = latest_tag {
+            Err(_) => {
                 yield Err(ShellError::labeled_error_with_secondary(
                     "Could not parse as YAML",
                     "input cannot be parsed as YAML",
                     &tag,
                     "value originates from here",
-                    &last_tag,
+                    &concat_string.tag,
                 ))
-            } ,
+            }
         }
     };
 

crates/nu-cli/src/commands/get.rs

@@ -0,0 +1,242 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use indexmap::set::IndexSet;
+use log::trace;
+use nu_errors::ShellError;
+use nu_protocol::{
+    did_you_mean, ColumnPath, PathMember, Primitive, ReturnSuccess, ReturnValue, Signature,
+    SyntaxShape, UnspannedPathMember, UntaggedValue, Value,
+};
+use nu_source::span_for_spanned_list;
+use nu_value_ext::get_data_by_column_path;
+
+pub struct Get;
+
+#[derive(Deserialize)]
+pub struct GetArgs {
+    rest: Vec<ColumnPath>,
+}
+
+impl WholeStreamCommand for Get {
+    fn name(&self) -> &str {
+        "get"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("get").rest(
+            SyntaxShape::ColumnPath,
+            "optionally return additional data by path",
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Open given cells as text."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, get)?.run()
+    }
+}
+
+pub fn get_column_path(path: &ColumnPath, obj: &Value) -> Result<Value, ShellError> {
+    let fields = path.clone();
+
+    get_data_by_column_path(
+        obj,
+        path,
+        Box::new(move |(obj_source, column_path_tried, error)| {
+            let path_members_span = span_for_spanned_list(fields.members().iter().map(|p| p.span));
+
+            match &obj_source.value {
+                UntaggedValue::Table(rows) => match column_path_tried {
+                    PathMember {
+                        unspanned: UnspannedPathMember::String(column),
+                        ..
+                    } => {
+                        let primary_label = format!("There isn't a column named '{}'", &column);
+
+                        let suggestions: IndexSet<_> = rows
+                            .iter()
+                            .filter_map(|r| did_you_mean(&r, &column_path_tried))
+                            .map(|s| s[0].1.to_owned())
+                            .collect();
+                        let mut existing_columns: IndexSet<_> = IndexSet::default();
+                        let mut names: Vec<String> = vec![];
+
+                        for row in rows {
+                            for field in row.data_descriptors() {
+                                if !existing_columns.contains(&field[..]) {
+                                    existing_columns.insert(field.clone());
+                                    names.push(field);
+                                }
+                            }
+                        }
+
+                        if names.is_empty() {
+                            return ShellError::labeled_error_with_secondary(
+                                "Unknown column",
+                                primary_label,
+                                column_path_tried.span,
+                                "Appears to contain rows. Try indexing instead.",
+                                column_path_tried.span.since(path_members_span),
+                            );
+                        } else {
+                            return ShellError::labeled_error_with_secondary(
+                                "Unknown column",
+                                primary_label,
+                                column_path_tried.span,
+                                format!(
+                                    "Perhaps you meant '{}'? Columns available: {}",
+                                    suggestions
+                                        .iter()
+                                        .map(|x| x.to_owned())
+                                        .collect::<Vec<String>>()
+                                        .join(","),
+                                    names.join(",")
+                                ),
+                                column_path_tried.span.since(path_members_span),
+                            );
+                        };
+                    }
+                    PathMember {
+                        unspanned: UnspannedPathMember::Int(idx),
+                        ..
+                    } => {
+                        let total = rows.len();
+
+                        let secondary_label = if total == 1 {
+                            "The table only has 1 row".to_owned()
+                        } else {
+                            format!("The table only has {} rows (0 to {})", total, total - 1)
+                        };
+
+                        return ShellError::labeled_error_with_secondary(
+                            "Row not found",
+                            format!("There isn't a row indexed at {}", idx),
+                            column_path_tried.span,
+                            secondary_label,
+                            column_path_tried.span.since(path_members_span),
+                        );
+                    }
+                },
+                UntaggedValue::Row(columns) => match column_path_tried {
+                    PathMember {
+                        unspanned: UnspannedPathMember::String(column),
+                        ..
+                    } => {
+                        let primary_label = format!("There isn't a column named '{}'", &column);
+
+                        if let Some(suggestions) = did_you_mean(&obj_source, column_path_tried) {
+                            return ShellError::labeled_error_with_secondary(
+                                "Unknown column",
+                                primary_label,
+                                column_path_tried.span,
+                                format!(
+                                    "Perhaps you meant '{}'? Columns available: {}",
+                                    suggestions[0].1,
+                                    &obj_source.data_descriptors().join(",")
+                                ),
+                                column_path_tried.span.since(path_members_span),
+                            );
+                        }
+                    }
+                    PathMember {
+                        unspanned: UnspannedPathMember::Int(idx),
+                        ..
+                    } => {
+                        return ShellError::labeled_error_with_secondary(
+                            "No rows available",
+                            format!("A row at '{}' can't be indexed.", &idx),
+                            column_path_tried.span,
+                            format!(
+                                "Appears to contain columns. Columns available: {}",
+                                columns.keys().join(",")
+                            ),
+                            column_path_tried.span.since(path_members_span),
+                        )
+                    }
+                },
+                _ => {}
+            }
+
+            if let Some(suggestions) = did_you_mean(&obj_source, column_path_tried) {
+                return ShellError::labeled_error(
+                    "Unknown column",
+                    format!("did you mean '{}'?", suggestions[0].1),
+                    column_path_tried.span.since(path_members_span),
+                );
+            }
+
+            error
+        }),
+    )
+}
+
+pub fn get(
+    GetArgs { rest: mut fields }: GetArgs,
+    RunnableContext { mut input, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    if fields.is_empty() {
+        let stream = async_stream! {
+            let mut vec = input.drain_vec().await;
+
+            let descs = nu_protocol::merge_descriptors(&vec);
+            for desc in descs {
+                yield ReturnSuccess::value(desc);
+            }
+        };
+
+        let stream: BoxStream<'static, ReturnValue> = stream.boxed();
+
+        Ok(stream.to_output_stream())
+    } else {
+        let member = fields.remove(0);
+        trace!("get {:?} {:?}", member, fields);
+        let stream = input
+            .values
+            .map(move |item| {
+                let mut result = VecDeque::new();
+
+                let member = vec![member.clone()];
+
+                let column_paths = vec![&member, &fields]
+                    .into_iter()
+                    .flatten()
+                    .collect::<Vec<&ColumnPath>>();
+
+                for path in column_paths {
+                    let res = get_column_path(&path, &item);
+
+                    match res {
+                        Ok(got) => match got {
+                            Value {
+                                value: UntaggedValue::Table(rows),
+                                ..
+                            } => {
+                                for item in rows {
+                                    result.push_back(ReturnSuccess::value(item.clone()));
+                                }
+                            }
+                            Value {
+                                value: UntaggedValue::Primitive(Primitive::Nothing),
+                                ..
+                            } => {}
+                            other => result.push_back(ReturnSuccess::value(other.clone())),
+                        },
+                        Err(reason) => result.push_back(ReturnSuccess::value(
+                            UntaggedValue::Error(reason).into_untagged_value(),
+                        )),
+                    }
+                }
+
+                futures::stream::iter(result)
+            })
+            .flatten();
+
+        Ok(stream.to_output_stream())
+    }
+}

crates/nu-cli/src/commands/group_by.rs

@@ -0,0 +1,223 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, TaggedDictBuilder, UntaggedValue, Value};
+use nu_source::Tagged;
+use nu_value_ext::get_data_by_key;
+
+pub struct GroupBy;
+
+#[derive(Deserialize)]
+pub struct GroupByArgs {
+    column_name: Tagged<String>,
+}
+
+impl WholeStreamCommand for GroupBy {
+    fn name(&self) -> &str {
+        "group-by"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("group-by").required(
+            "column_name",
+            SyntaxShape::String,
+            "the name of the column to group by",
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Creates a new table with the data from the table rows grouped by the column given."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, group_by)?.run()
+    }
+}
+
+pub fn group_by(
+    GroupByArgs { column_name }: GroupByArgs,
+    RunnableContext { input, name, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let stream = async_stream! {
+        let values: Vec<Value> = input.values.collect().await;
+
+        if values.is_empty() {
+            yield Err(ShellError::labeled_error(
+                    "Expected table from pipeline",
+                    "requires a table input",
+                    column_name.span()
+                ))
+        } else {
+            match group(&column_name, values, name) {
+                Ok(grouped) => yield ReturnSuccess::value(grouped),
+                Err(err) => yield Err(err)
+            }
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}
+
+pub fn group(
+    column_name: &Tagged<String>,
+    values: Vec<Value>,
+    tag: impl Into<Tag>,
+) -> Result<Value, ShellError> {
+    let tag = tag.into();
+
+    let mut groups: indexmap::IndexMap<String, Vec<Value>> = indexmap::IndexMap::new();
+
+    for value in values {
+        let group_key = get_data_by_key(&value, column_name.borrow_spanned());
+
+        if let Some(group_key) = group_key {
+            let group_key = group_key.as_string()?.to_string();
+            let group = groups.entry(group_key).or_insert(vec![]);
+            group.push(value);
+        } else {
+            let possibilities = value.data_descriptors();
+
+            let mut possible_matches: Vec<_> = possibilities
+                .iter()
+                .map(|x| (natural::distance::levenshtein_distance(x, column_name), x))
+                .collect();
+
+            possible_matches.sort();
+
+            if !possible_matches.is_empty() {
+                return Err(ShellError::labeled_error(
+                    "Unknown column",
+                    format!("did you mean '{}'?", possible_matches[0].1),
+                    column_name.tag(),
+                ));
+            } else {
+                return Err(ShellError::labeled_error(
+                    "Unknown column",
+                    "row does not contain this column",
+                    column_name.tag(),
+                ));
+            }
+        }
+    }
+
+    let mut out = TaggedDictBuilder::new(&tag);
+
+    for (k, v) in groups.iter() {
+        out.insert_untagged(k, UntaggedValue::table(v));
+    }
+
+    Ok(out.into_value())
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::commands::group_by::group;
+    use indexmap::IndexMap;
+    use nu_errors::ShellError;
+    use nu_protocol::{UntaggedValue, Value};
+    use nu_source::*;
+
+    fn string(input: impl Into<String>) -> Value {
+        UntaggedValue::string(input.into()).into_untagged_value()
+    }
+
+    fn row(entries: IndexMap<String, Value>) -> Value {
+        UntaggedValue::row(entries).into_untagged_value()
+    }
+
+    fn table(list: &[Value]) -> Value {
+        UntaggedValue::table(list).into_untagged_value()
+    }
+
+    fn nu_releases_commiters() -> Vec<Value> {
+        vec![
+            row(
+                indexmap! {"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => string("August 23-2019")},
+            ),
+            row(
+                indexmap! {"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => string("August 23-2019")},
+            ),
+            row(
+                indexmap! {"name".into() => string("YK"), "country".into() => string("US"), "date".into() => string("October 10-2019")},
+            ),
+            row(
+                indexmap! {"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => string("Sept 24-2019")},
+            ),
+            row(
+                indexmap! {"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => string("October 10-2019")},
+            ),
+            row(
+                indexmap! {"name".into() => string("YK"), "country".into() => string("US"), "date".into() => string("Sept 24-2019")},
+            ),
+            row(
+                indexmap! {"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => string("October 10-2019")},
+            ),
+            row(
+                indexmap! {"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => string("Sept 24-2019")},
+            ),
+            row(
+                indexmap! {"name".into() => string("YK"), "country".into() => string("US"), "date".into() => string("August 23-2019")},
+            ),
+        ]
+    }
+
+    #[test]
+    fn groups_table_by_date_column() -> Result<(), ShellError> {
+        let for_key = String::from("date").tagged_unknown();
+
+        assert_eq!(
+            group(&for_key, nu_releases_commiters(), Tag::unknown())?,
+            row(indexmap! {
+                "August 23-2019".into() =>  table(&[
+                    row(indexmap!{"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => string("August 23-2019")}),
+                    row(indexmap!{"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => string("August 23-2019")}),
+                    row(indexmap!{"name".into() => string("YK"), "country".into() => string("US"), "date".into() => string("August 23-2019")})
+                ]),
+                "October 10-2019".into() =>  table(&[
+                    row(indexmap!{"name".into() => string("YK"), "country".into() => string("US"), "date".into() => string("October 10-2019")}),
+                    row(indexmap!{"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => string("October 10-2019")}),
+                    row(indexmap!{"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => string("October 10-2019")})
+                ]),
+                "Sept 24-2019".into() =>  table(&[
+                    row(indexmap!{"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => string("Sept 24-2019")}),
+                    row(indexmap!{"name".into() => string("YK"), "country".into() => string("US"), "date".into() => string("Sept 24-2019")}),
+                    row(indexmap!{"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => string("Sept 24-2019")})
+                ]),
+            })
+        );
+
+        Ok(())
+    }
+
+    #[test]
+    fn groups_table_by_country_column() -> Result<(), ShellError> {
+        let for_key = String::from("country").tagged_unknown();
+
+        assert_eq!(
+            group(&for_key, nu_releases_commiters(), Tag::unknown())?,
+            row(indexmap! {
+                "EC".into() =>  table(&[
+                    row(indexmap!{"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => string("August 23-2019")}),
+                    row(indexmap!{"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => string("Sept 24-2019")}),
+                    row(indexmap!{"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => string("October 10-2019")})
+                ]),
+                "NZ".into() =>  table(&[
+                    row(indexmap!{"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => string("August 23-2019")}),
+                    row(indexmap!{"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => string("October 10-2019")}),
+                    row(indexmap!{"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => string("Sept 24-2019")})
+                ]),
+                "US".into() =>  table(&[
+                    row(indexmap!{"name".into() => string("YK"), "country".into() => string("US"), "date".into() => string("October 10-2019")}),
+                    row(indexmap!{"name".into() => string("YK"), "country".into() => string("US"), "date".into() => string("Sept 24-2019")}),
+                    row(indexmap!{"name".into() => string("YK"), "country".into() => string("US"), "date".into() => string("August 23-2019")}),
+                ]),
+            })
+        );
+
+        Ok(())
+    }
+}

crates/nu-cli/src/commands/headers.rs

@@ -0,0 +1,80 @@
+use crate::commands::WholeStreamCommand;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use futures::stream::StreamExt;
+use indexmap::IndexMap;
+use nu_errors::ShellError;
+use nu_protocol::Dictionary;
+use nu_protocol::{ReturnSuccess, Signature, UntaggedValue, Value};
+
+pub struct Headers;
+#[derive(Deserialize)]
+pub struct HeadersArgs {}
+
+impl WholeStreamCommand for Headers {
+    fn name(&self) -> &str {
+        "headers"
+    }
+    fn signature(&self) -> Signature {
+        Signature::build("headers")
+    }
+    fn usage(&self) -> &str {
+        "Use the first row of the table as column names"
+    }
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, headers)?.run()
+    }
+}
+
+pub fn headers(
+    HeadersArgs {}: HeadersArgs,
+    RunnableContext { input, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let stream = async_stream! {
+        let rows: Vec<Value> = input.values.collect().await;
+
+        if rows.len() < 1 {
+            yield Err(ShellError::untagged_runtime_error("Couldn't find headers, was the input a properly formatted, non-empty table?"));
+        }
+
+        //the headers are the first row in the table
+        let headers: Vec<String> = match &rows[0].value {
+            UntaggedValue::Row(d) => {
+                Ok(d.entries.iter().map(|(k, v)| {
+                    match v.as_string() {
+                        Ok(s) => s,
+                        Err(_) => { //If a cell that should contain a header name is empty, we name the column Column[index]
+                            match d.entries.get_full(k) {
+                                Some((index, _, _)) => format!("Column{}", index),
+                                None => "unknownColumn".to_string()
+                            }
+                        }
+                    }
+                }).collect())
+            }
+            _ => Err(ShellError::unexpected_eof("Could not get headers, is the table empty?", rows[0].tag.span))
+        }?;
+
+        //Each row is a dictionary with the headers as keys
+        for r in rows.iter().skip(1) {
+            match &r.value {
+                UntaggedValue::Row(d) => {
+                    let mut i = 0;
+                    let mut entries = IndexMap::new();
+                    for (_, v) in d.entries.iter() {
+                        entries.insert(headers[i].clone(), v.clone());
+                        i += 1;
+                    }
+                    yield Ok(ReturnSuccess::Value(UntaggedValue::Row(Dictionary{entries}).into_value(r.tag.clone())))
+                }
+                _ => yield Err(ShellError::unexpected_eof("Couldn't iterate through rows, was the input a properly formatted table?", r.tag.span))
+            }
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/help.rs

@@ -0,0 +1,242 @@
+use crate::commands::PerItemCommand;
+use crate::data::command_dict;
+
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{
+    CallInfo, NamedType, PositionalType, Primitive, ReturnSuccess, Signature, SyntaxShape,
+    TaggedDictBuilder, UntaggedValue, Value,
+};
+use nu_source::SpannedItem;
+use nu_value_ext::get_data_by_key;
+
+pub struct Help;
+
+impl PerItemCommand for Help {
+    fn name(&self) -> &str {
+        "help"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("help").rest(SyntaxShape::Any, "the name of command(s) to get help on")
+    }
+
+    fn usage(&self) -> &str {
+        "Display help information about commands."
+    }
+
+    fn run(
+        &self,
+        call_info: &CallInfo,
+        registry: &CommandRegistry,
+        _raw_args: &RawCommandArgs,
+        _input: Value,
+    ) -> Result<OutputStream, ShellError> {
+        let tag = &call_info.name_tag;
+
+        match call_info.args.nth(0) {
+            Some(Value {
+                value: UntaggedValue::Primitive(Primitive::String(document)),
+                tag,
+            }) => {
+                let mut help = VecDeque::new();
+                if document == "commands" {
+                    let mut sorted_names = registry.names();
+                    sorted_names.sort();
+                    for cmd in sorted_names {
+                        let mut short_desc = TaggedDictBuilder::new(tag.clone());
+                        let value = command_dict(
+                            registry.get_command(&cmd).ok_or_else(|| {
+                                ShellError::labeled_error(
+                                    format!("Could not load {}", cmd),
+                                    "could not load command",
+                                    tag,
+                                )
+                            })?,
+                            tag.clone(),
+                        );
+
+                        short_desc.insert_untagged("name", cmd);
+                        short_desc.insert_untagged(
+                            "description",
+                            get_data_by_key(&value, "usage".spanned_unknown())
+                                .ok_or_else(|| {
+                                    ShellError::labeled_error(
+                                        "Expected a usage key",
+                                        "expected a 'usage' key",
+                                        &value.tag,
+                                    )
+                                })?
+                                .as_string()?,
+                        );
+
+                        help.push_back(ReturnSuccess::value(short_desc.into_value()));
+                    }
+                } else if let Some(command) = registry.get_command(document) {
+                    return Ok(
+                        get_help(&command.name(), &command.usage(), command.signature()).into(),
+                    );
+                }
+                let help = futures::stream::iter(help);
+                Ok(help.to_output_stream())
+            }
+            _ => {
+                let msg = r#"Welcome to Nushell.
+
+Here are some tips to help you get started.
+  * help commands - list all available commands
+  * help <command name> - display help about a particular command
+
+Nushell works on the idea of a "pipeline". Pipelines are commands connected with the '|' character.
+Each stage in the pipeline works together to load, parse, and display information to you.
+
+[Examples]
+
+List the files in the current directory, sorted by size:
+    ls | sort-by size
+
+Get information about the current system:
+    sys | get host
+
+Get the processes on your system actively using CPU:
+    ps | where cpu > 0
+
+You can also learn more at https://www.nushell.sh/book/"#;
+
+                let output_stream = futures::stream::iter(vec![ReturnSuccess::value(
+                    UntaggedValue::string(msg).into_value(tag),
+                )]);
+
+                Ok(output_stream.to_output_stream())
+            }
+        }
+    }
+}
+
+pub(crate) fn get_help(
+    cmd_name: &str,
+    cmd_usage: &str,
+    cmd_sig: Signature,
+) -> impl Into<OutputStream> {
+    let mut help = VecDeque::new();
+    let mut long_desc = String::new();
+
+    long_desc.push_str(&cmd_usage);
+    long_desc.push_str("\n");
+
+    let signature = cmd_sig;
+
+    let mut one_liner = String::new();
+    one_liner.push_str(&signature.name);
+    one_liner.push_str(" ");
+
+    for positional in &signature.positional {
+        match &positional.0 {
+            PositionalType::Mandatory(name, _m) => {
+                one_liner.push_str(&format!("<{}> ", name));
+            }
+            PositionalType::Optional(name, _o) => {
+                one_liner.push_str(&format!("({}) ", name));
+            }
+        }
+    }
+
+    if signature.rest_positional.is_some() {
+        one_liner.push_str(" ...args");
+    }
+
+    if !signature.named.is_empty() {
+        one_liner.push_str("{flags} ");
+    }
+
+    long_desc.push_str(&format!("\nUsage:\n  > {}\n", one_liner));
+
+    if !signature.positional.is_empty() || signature.rest_positional.is_some() {
+        long_desc.push_str("\nparameters:\n");
+        for positional in signature.positional {
+            match positional.0 {
+                PositionalType::Mandatory(name, _m) => {
+                    long_desc.push_str(&format!("  <{}> {}\n", name, positional.1));
+                }
+                PositionalType::Optional(name, _o) => {
+                    long_desc.push_str(&format!("  ({}) {}\n", name, positional.1));
+                }
+            }
+        }
+
+        if let Some(rest_positional) = signature.rest_positional {
+            long_desc.push_str(&format!("  ...args: {}\n", rest_positional.1));
+        }
+    }
+    if !signature.named.is_empty() {
+        long_desc.push_str("\nflags:\n");
+        for (flag, ty) in signature.named {
+            let msg = match ty.0 {
+                NamedType::Switch(s) => {
+                    if let Some(c) = s {
+                        format!(
+                            "  -{}, --{}{} {}\n",
+                            c,
+                            flag,
+                            if !ty.1.is_empty() { ":" } else { "" },
+                            ty.1
+                        )
+                    } else {
+                        format!(
+                            "  --{}{} {}\n",
+                            flag,
+                            if !ty.1.is_empty() { ":" } else { "" },
+                            ty.1
+                        )
+                    }
+                }
+                NamedType::Mandatory(s, m) => {
+                    if let Some(c) = s {
+                        format!(
+                            "  -{}, --{} <{}> (required parameter){} {}\n",
+                            c,
+                            flag,
+                            m.display(),
+                            if !ty.1.is_empty() { ":" } else { "" },
+                            ty.1
+                        )
+                    } else {
+                        format!(
+                            "  --{} <{}> (required parameter){} {}\n",
+                            flag,
+                            m.display(),
+                            if !ty.1.is_empty() { ":" } else { "" },
+                            ty.1
+                        )
+                    }
+                }
+                NamedType::Optional(s, o) => {
+                    if let Some(c) = s {
+                        format!(
+                            "  -{}, --{} <{}>{} {}\n",
+                            c,
+                            flag,
+                            o.display(),
+                            if !ty.1.is_empty() { ":" } else { "" },
+                            ty.1
+                        )
+                    } else {
+                        format!(
+                            "  --{} <{}>{} {}\n",
+                            flag,
+                            o.display(),
+                            if !ty.1.is_empty() { ":" } else { "" },
+                            ty.1
+                        )
+                    }
+                }
+            };
+            long_desc.push_str(&msg);
+        }
+    }
+
+    help.push_back(ReturnSuccess::value(
+        UntaggedValue::string(long_desc).into_value(Tag::from((0, cmd_name.len(), None))),
+    ));
+    help
+}

crates/nu-cli/src/commands/histogram.rs

@@ -0,0 +1,160 @@
+use crate::commands::group_by::group;
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use crate::utils::data_processing::{columns_sorted, evaluate, map_max, reduce, t_sort};
+use nu_errors::ShellError;
+use nu_protocol::{
+    Primitive, ReturnSuccess, Signature, SyntaxShape, TaggedDictBuilder, UntaggedValue, Value,
+};
+use nu_source::Tagged;
+use num_traits::{ToPrimitive, Zero};
+
+pub struct Histogram;
+
+#[derive(Deserialize)]
+pub struct HistogramArgs {
+    column_name: Tagged<String>,
+    rest: Vec<Tagged<String>>,
+}
+
+impl WholeStreamCommand for Histogram {
+    fn name(&self) -> &str {
+        "histogram"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("histogram")
+            .required(
+                "column_name",
+                SyntaxShape::String,
+                "the name of the column to graph by",
+            )
+            .rest(
+                SyntaxShape::Member,
+                "column name to give the histogram's frequency column",
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "Creates a new table with a histogram based on the column name passed in."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, histogram)?.run()
+    }
+}
+
+pub fn histogram(
+    HistogramArgs { column_name, rest }: HistogramArgs,
+    RunnableContext { input, name, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let stream = async_stream! {
+        let values: Vec<Value> = input.values.collect().await;
+
+        let Tagged { item: group_by, .. } = column_name.clone();
+
+        let groups = group(&column_name, values, &name)?;
+        let group_labels = columns_sorted(Some(group_by.clone()), &groups, &name);
+        let sorted = t_sort(Some(group_by.clone()), None, &groups, &name)?;
+        let evaled = evaluate(&sorted, None, &name)?;
+        let reduced = reduce(&evaled, None, &name)?;
+        let maxima = map_max(&reduced, None, &name)?;
+        let percents = percentages(&reduced, maxima, &name)?;
+
+        match percents {
+            Value {
+                value: UntaggedValue::Table(datasets),
+                ..
+            } => {
+
+                let mut idx = 0;
+
+                let column_names_supplied: Vec<_> = rest.iter().map(|f| f.item.clone()).collect();
+
+                let frequency_column_name = if column_names_supplied.is_empty() {
+                    "frequency".to_string()
+                } else {
+                    column_names_supplied[0].clone()
+                };
+
+                let column = (*column_name).clone();
+
+                if let Value { value: UntaggedValue::Table(start), .. } = datasets.get(0).ok_or_else(|| ShellError::labeled_error("Unable to load dataset", "unabled to load dataset", &name))? {
+                    for percentage in start.iter() {
+
+                        let mut fact = TaggedDictBuilder::new(&name);
+                        let value: Tagged<String> = group_labels.get(idx).ok_or_else(|| ShellError::labeled_error("Unable to load group labels", "unabled to load group labels", &name))?.clone();
+                        fact.insert_value(&column, UntaggedValue::string(value.item).into_value(value.tag));
+
+                        if let Value { value: UntaggedValue::Primitive(Primitive::Int(ref num)), ref tag } = percentage.clone() {
+                            let string = std::iter::repeat("*").take(num.to_i32().ok_or_else(|| ShellError::labeled_error("Expected a number", "expected a number", tag))? as usize).collect::<String>();
+                            fact.insert_untagged(&frequency_column_name, UntaggedValue::string(string));
+                        }
+
+                        idx += 1;
+
+                        yield ReturnSuccess::value(fact.into_value());
+                    }
+                }
+            }
+            _ => {}
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}
+
+fn percentages(values: &Value, max: Value, tag: impl Into<Tag>) -> Result<Value, ShellError> {
+    let tag = tag.into();
+
+    let results: Value = match values {
+        Value {
+            value: UntaggedValue::Table(datasets),
+            ..
+        } => {
+            let datasets: Vec<_> = datasets
+                .iter()
+                .map(|subsets| match subsets {
+                    Value {
+                        value: UntaggedValue::Table(data),
+                        ..
+                    } => {
+                        let data = data
+                            .iter()
+                            .map(|d| match d {
+                                Value {
+                                    value: UntaggedValue::Primitive(Primitive::Int(n)),
+                                    ..
+                                } => {
+                                    let max = match &max {
+                                        Value {
+                                            value: UntaggedValue::Primitive(Primitive::Int(maxima)),
+                                            ..
+                                        } => maxima.clone(),
+                                        _ => Zero::zero(),
+                                    };
+
+                                    let n = (n * 100) / max;
+
+                                    UntaggedValue::int(n).into_value(&tag)
+                                }
+                                _ => UntaggedValue::int(0).into_value(&tag),
+                            })
+                            .collect::<Vec<_>>();
+                        UntaggedValue::Table(data).into_value(&tag)
+                    }
+                    _ => UntaggedValue::Table(vec![]).into_value(&tag),
+                })
+                .collect();
+
+            UntaggedValue::Table(datasets).into_value(&tag)
+        }
+        other => other.clone(),
+    };
+
+    Ok(results)
+}

crates/nu-cli/src/commands/history.rs

@@ -0,0 +1,49 @@
+use crate::cli::History as HistoryFile;
+use crate::commands::PerItemCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CallInfo, ReturnSuccess, Signature, UntaggedValue, Value};
+use std::fs::File;
+use std::io::{BufRead, BufReader};
+
+pub struct History;
+
+impl PerItemCommand for History {
+    fn name(&self) -> &str {
+        "history"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("history")
+    }
+
+    fn usage(&self) -> &str {
+        "Display command history."
+    }
+
+    fn run(
+        &self,
+        call_info: &CallInfo,
+        _registry: &CommandRegistry,
+        _raw_args: &RawCommandArgs,
+        _input: Value,
+    ) -> Result<OutputStream, ShellError> {
+        let tag = call_info.name_tag.clone();
+
+        let stream = async_stream! {
+            let history_path = HistoryFile::path();
+            let file = File::open(history_path);
+            if let Ok(file) = file {
+                let reader = BufReader::new(file);
+                for line in reader.lines() {
+                    if let Ok(line) = line {
+                        yield ReturnSuccess::value(UntaggedValue::string(line).into_value(tag.clone()));
+                    }
+                }
+            } else {
+                yield Err(ShellError::labeled_error("Could not open history", "history file could not be opened", tag.clone()));
+            }
+        };
+        Ok(stream.to_output_stream())
+    }
+}

crates/nu-cli/src/commands/insert.rs

@@ -0,0 +1,66 @@
+use crate::commands::PerItemCommand;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CallInfo, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_value_ext::ValueExt;
+
+pub struct Insert;
+
+impl PerItemCommand for Insert {
+    fn name(&self) -> &str {
+        "insert"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("insert")
+            .required(
+                "column",
+                SyntaxShape::ColumnPath,
+                "the column name to insert",
+            )
+            .required(
+                "value",
+                SyntaxShape::String,
+                "the value to give the cell(s)",
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "Edit an existing column to have a new value."
+    }
+
+    fn run(
+        &self,
+        call_info: &CallInfo,
+        _registry: &CommandRegistry,
+        _raw_args: &RawCommandArgs,
+        value: Value,
+    ) -> Result<OutputStream, ShellError> {
+        let value_tag = value.tag();
+        let field = call_info.args.expect_nth(0)?.as_column_path()?;
+        let replacement = call_info.args.expect_nth(1)?.tagged_unknown();
+
+        let stream = match value {
+            obj
+            @
+            Value {
+                value: UntaggedValue::Row(_),
+                ..
+            } => match obj.insert_data_at_column_path(&field, replacement.item.clone()) {
+                Ok(v) => futures::stream::iter(vec![Ok(ReturnSuccess::Value(v))]),
+                Err(err) => return Err(err),
+            },
+
+            _ => {
+                return Err(ShellError::labeled_error(
+                    "Unrecognized type in stream",
+                    "original value",
+                    value_tag,
+                ))
+            }
+        };
+
+        Ok(stream.to_output_stream())
+    }
+}

crates/nu-cli/src/commands/kill.rs

@@ -0,0 +1,104 @@
+use crate::commands::command::RunnablePerItemContext;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CallInfo, Signature, SyntaxShape, Value};
+use nu_source::Tagged;
+use std::process::{Command, Stdio};
+
+pub struct Kill;
+
+#[derive(Deserialize)]
+pub struct KillArgs {
+    pub pid: Tagged<u64>,
+    pub rest: Vec<Tagged<u64>>,
+    pub force: Tagged<bool>,
+    pub quiet: Tagged<bool>,
+}
+
+impl PerItemCommand for Kill {
+    fn name(&self) -> &str {
+        "kill"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("kill")
+            .required(
+                "pid",
+                SyntaxShape::Int,
+                "process id of process that is to be killed",
+            )
+            .rest(SyntaxShape::Int, "rest of processes to kill")
+            .switch("force", "forcefully kill the process", Some('f'))
+            .switch("quiet", "won't print anything to the console", Some('q'))
+    }
+
+    fn usage(&self) -> &str {
+        "Kill a process using the process id."
+    }
+
+    fn run(
+        &self,
+        call_info: &CallInfo,
+        _registry: &CommandRegistry,
+        raw_args: &RawCommandArgs,
+        _input: Value,
+    ) -> Result<OutputStream, ShellError> {
+        call_info
+            .process(&raw_args.shell_manager, raw_args.ctrl_c.clone(), kill)?
+            .run()
+    }
+}
+
+fn kill(
+    KillArgs {
+        pid,
+        rest,
+        force,
+        quiet,
+    }: KillArgs,
+    _context: &RunnablePerItemContext,
+) -> Result<OutputStream, ShellError> {
+    let mut cmd = if cfg!(windows) {
+        let mut cmd = Command::new("taskkill");
+
+        if *force {
+            cmd.arg("/F");
+        }
+
+        cmd.arg("/PID");
+        cmd.arg(pid.item().to_string());
+
+        // each pid must written as `/PID 0` otherwise
+        // taskkill will act as `killall` unix command
+        for id in &rest {
+            cmd.arg("/PID");
+            cmd.arg(id.item().to_string());
+        }
+
+        cmd
+    } else {
+        let mut cmd = Command::new("kill");
+
+        if *force {
+            cmd.arg("-9");
+        }
+
+        cmd.arg(pid.item().to_string());
+
+        cmd.args(rest.iter().map(move |id| id.item().to_string()));
+
+        cmd
+    };
+
+    // pipe everything to null
+    if *quiet {
+        cmd.stdin(Stdio::null())
+            .stdout(Stdio::null())
+            .stderr(Stdio::null());
+    }
+
+    cmd.status().expect("failed to execute shell command");
+
+    Ok(OutputStream::empty())
+}

crates/nu-cli/src/commands/last.rs

@@ -1,7 +1,9 @@
 use crate::commands::WholeStreamCommand;
-use crate::errors::ShellError;
-use crate::parser::CommandRegistry;
+use crate::context::CommandRegistry;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, Value};
+use nu_source::Tagged;
 
 pub struct Last;
 
@@ -16,7 +18,11 @@ impl WholeStreamCommand for Last {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("last").optional("rows", SyntaxShape::Number)
+        Signature::build("last").optional(
+            "rows",
+            SyntaxShape::Number,
+            "starting from the back, the number of rows to return",
+        )
     }
 
     fn usage(&self) -> &str {
@@ -46,7 +52,7 @@ fn last(LastArgs { rows }: LastArgs, context: RunnableContext) -> Result<OutputS
         if count < v.len() {
             let k = v.len() - count;
             for x in v[k..].iter() {
-                let y: Tagged<Value> = x.clone();
+                let y: Value = x.clone();
                 yield ReturnSuccess::value(y)
             }
         }

crates/nu-cli/src/commands/lines.rs

@@ -0,0 +1,116 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, UntaggedValue, Value};
+
+pub struct Lines;
+
+impl WholeStreamCommand for Lines {
+    fn name(&self) -> &str {
+        "lines"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("lines")
+    }
+
+    fn usage(&self) -> &str {
+        "Split single string into rows, one per line."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        lines(args, registry)
+    }
+}
+
+fn ends_with_line_ending(st: &str) -> bool {
+    let mut temp = st.to_string();
+    let last = temp.pop();
+    if let Some(c) = last {
+        c == '\n'
+    } else {
+        false
+    }
+}
+
+fn lines(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStream, ShellError> {
+    let args = args.evaluate_once(registry)?;
+    let tag = args.name_tag();
+    let name_span = tag.span;
+    let mut input = args.input;
+
+    let mut leftover = vec![];
+    let mut leftover_string = String::new();
+    let stream = async_stream! {
+        loop {
+            match input.values.next().await {
+                Some(Value { value: UntaggedValue::Primitive(Primitive::String(st)), ..}) => {
+                    let mut st = leftover_string.clone() + &st;
+                    leftover.clear();
+
+                    let mut lines: Vec<String> = st.lines().map(|x| x.to_string()).collect();
+
+                    if !ends_with_line_ending(&st) {
+                        if let Some(last) = lines.pop() {
+                            leftover_string = last;
+                        } else {
+                            leftover_string.clear();
+                        }
+                    } else {
+                        leftover_string.clear();
+                    }
+
+                    let success_lines: Vec<_> = lines.iter().map(|x| ReturnSuccess::value(UntaggedValue::line(x).into_untagged_value())).collect();
+                    yield futures::stream::iter(success_lines)
+                }
+                Some(Value { value: UntaggedValue::Primitive(Primitive::Line(st)), ..}) => {
+                    let mut st = leftover_string.clone() + &st;
+                    leftover.clear();
+
+                    let mut lines: Vec<String> = st.lines().map(|x| x.to_string()).collect();
+                    if !ends_with_line_ending(&st) {
+                        if let Some(last) = lines.pop() {
+                            leftover_string = last;
+                        } else {
+                            leftover_string.clear();
+                        }
+                    } else {
+                        leftover_string.clear();
+                    }
+
+                    let success_lines: Vec<_> = lines.iter().map(|x| ReturnSuccess::value(UntaggedValue::line(x).into_untagged_value())).collect();
+                    yield futures::stream::iter(success_lines)
+                }
+                Some( Value { tag: value_span, ..}) => {
+                    yield futures::stream::iter(vec![Err(ShellError::labeled_error_with_secondary(
+                        "Expected a string from pipeline",
+                        "requires string input",
+                        name_span,
+                        "value originates from here",
+                        value_span,
+                    ))]);
+                }
+                None => {
+                    if !leftover.is_empty() {
+                        let mut st = leftover_string.clone();
+                        if let Ok(extra) = String::from_utf8(leftover) {
+                            st.push_str(&extra);
+                        }
+                        yield futures::stream::iter(vec![ReturnSuccess::value(UntaggedValue::string(st).into_untagged_value())])
+                    }
+                    break;
+                }
+            }
+        }
+        if !leftover_string.is_empty() {
+            yield futures::stream::iter(vec![ReturnSuccess::value(UntaggedValue::string(leftover_string).into_untagged_value())]);
+        }
+    }
+    .flatten();
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/ls.rs

@@ -0,0 +1,70 @@
+use crate::commands::command::RunnablePerItemContext;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CallInfo, Signature, SyntaxShape, Value};
+use nu_source::Tagged;
+use std::path::PathBuf;
+
+pub struct Ls;
+
+#[derive(Deserialize)]
+pub struct LsArgs {
+    pub path: Option<Tagged<PathBuf>>,
+    pub all: bool,
+    pub full: bool,
+    #[serde(rename = "short-names")]
+    pub short_names: bool,
+    #[serde(rename = "with-symlink-targets")]
+    pub with_symlink_targets: bool,
+}
+
+impl PerItemCommand for Ls {
+    fn name(&self) -> &str {
+        "ls"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("ls")
+            .optional(
+                "path",
+                SyntaxShape::Pattern,
+                "a path to get the directory contents from",
+            )
+            .switch("all", "also show hidden files", Some('a'))
+            .switch(
+                "full",
+                "list all available columns for each entry",
+                Some('f'),
+            )
+            .switch(
+                "short-names",
+                "only print the file names and not the path",
+                Some('s'),
+            )
+            .switch(
+                "with-symlink-targets",
+                "display the paths to the target files that symlinks point to",
+                Some('w'),
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "View the contents of the current or given path."
+    }
+
+    fn run(
+        &self,
+        call_info: &CallInfo,
+        _registry: &CommandRegistry,
+        raw_args: &RawCommandArgs,
+        _input: Value,
+    ) -> Result<OutputStream, ShellError> {
+        call_info
+            .process(&raw_args.shell_manager, raw_args.ctrl_c.clone(), ls)?
+            .run()
+    }
+}
+
+fn ls(args: LsArgs, context: &RunnablePerItemContext) -> Result<OutputStream, ShellError> {
+    context.shell_manager.ls(args, context)
+}

crates/nu-cli/src/commands/macros.rs

@@ -45,8 +45,8 @@ macro_rules! command {
                 stringify!($config_name)
             }
 
-            fn config(&self) -> $crate::parser::registry::Signature {
-                $crate::parser::registry::Signature {
+            fn config(&self) -> $nu_parser::registry::Signature {
+                $nu_parser::registry::Signature {
                     name: self.name().to_string(),
                     positional: vec![$($mandatory_positional)*],
                     rest_positional: false,
@@ -54,13 +54,13 @@ macro_rules! command {
                     is_sink: false,
 
                     named: {
-                        use $crate::parser::registry::NamedType;
+                        use $nu_parser::registry::NamedType;
 
                         #[allow(unused_mut)]
                         let mut named: indexmap::IndexMap<String, NamedType> = indexmap::IndexMap::new();
 
                         $(
-                            named.insert(stringify!($named_param).to_string(), $crate::parser::registry::NamedType::$named_kind);
+                            named.insert(stringify!($named_param).to_string(), $nu_parser::registry::NamedType::$named_kind);
                         )*
 
                         named
@@ -114,7 +114,7 @@ macro_rules! command {
                 $($extract)* {
                     use std::convert::TryInto;
 
-                    $args.get(stringify!($param_name)).clone().try_into()?
+                    $args.get(stringify!($param_name)).try_into()?
                 }
             }
         );
@@ -164,7 +164,7 @@ macro_rules! command {
                 $($extract)* {
                     use std::convert::TryInto;
 
-                    $args.get(stringify!($param_name)).clone().try_into()?
+                    $args.get(stringify!($param_name)).try_into()?
                 }
             }
         );
@@ -214,7 +214,7 @@ macro_rules! command {
                 $($extract)* {
                     use std::convert::TryInto;
 
-                    $args.get(stringify!($param_name)).clone().try_into()?
+                    $args.get(stringify!($param_name)).try_into()?
                 }
             }
         );
@@ -250,7 +250,7 @@ macro_rules! command {
             Rest { $($rest)* }
             Signature {
                 name: $config_name,
-                mandatory_positional: vec![ $($mandatory_positional)* $crate::parser::registry::PositionalType::mandatory_block(
+                mandatory_positional: vec![ $($mandatory_positional)* $nu_parser::registry::PositionalType::mandatory_block(
                     stringify!($param_name)
                 ), ],
                 optional_positional: vec![ $($optional_positional)* ],
@@ -305,7 +305,7 @@ macro_rules! command {
             Rest { $($rest)* }
             Signature {
                 name: $config_name,
-                mandatory_positional: vec![ $($mandatory_positional)* $crate::parser::registry::PositionalType::mandatory(
+                mandatory_positional: vec![ $($mandatory_positional)* $nu_parser::registry::PositionalType::mandatory(
                     stringify!($param_name), <$param_kind>::syntax_type()
                 ), ],
                 optional_positional: vec![ $($optional_positional)* ],

crates/nu-cli/src/commands/map_max_by.rs

@@ -0,0 +1,74 @@
+use crate::commands::WholeStreamCommand;
+use crate::data::value;
+use crate::prelude::*;
+use crate::utils::data_processing::map_max;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_source::Tagged;
+use num_traits::cast::ToPrimitive;
+
+pub struct MapMaxBy;
+
+#[derive(Deserialize)]
+pub struct MapMaxByArgs {
+    column_name: Option<Tagged<String>>,
+}
+
+impl WholeStreamCommand for MapMaxBy {
+    fn name(&self) -> &str {
+        "map-max-by"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("map-max-by").named(
+            "column_name",
+            SyntaxShape::String,
+            "the name of the column to map-max the table's rows",
+            Some('c'),
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Creates a new table with the data from the tables rows maxed by the column given."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, map_max_by)?.run()
+    }
+}
+
+pub fn map_max_by(
+    MapMaxByArgs { column_name }: MapMaxByArgs,
+    RunnableContext { input, name, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let stream = async_stream! {
+        let values: Vec<Value> = input.values.collect().await;
+
+
+        if values.is_empty() {
+            yield Err(ShellError::labeled_error(
+                    "Expected table from pipeline",
+                    "requires a table input",
+                    name
+                ))
+        } else {
+
+            let map_by_column = if let Some(column_to_map) = column_name {
+                Some(column_to_map.item().clone())
+            } else {
+                None
+            };
+
+            match map_max(&values[0], map_by_column, name) {
+                Ok(table_maxed) => yield ReturnSuccess::value(table_maxed),
+                Err(err) => yield Err(err)
+            }
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/mkdir.rs

@@ -1,7 +1,9 @@
 use crate::commands::command::RunnablePerItemContext;
-use crate::errors::ShellError;
-use crate::parser::registry::{CommandRegistry, Signature};
+use crate::context::CommandRegistry;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CallInfo, Signature, SyntaxShape, Value};
+use nu_source::Tagged;
 use std::path::PathBuf;
 
 pub struct Mkdir;
@@ -17,7 +19,7 @@ impl PerItemCommand for Mkdir {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("mkdir").rest(SyntaxShape::Path)
+        Signature::build("mkdir").rest(SyntaxShape::Path, "the name(s) of the path(s) to create")
     }
 
     fn usage(&self) -> &str {
@@ -29,9 +31,11 @@ impl PerItemCommand for Mkdir {
         call_info: &CallInfo,
         _registry: &CommandRegistry,
         raw_args: &RawCommandArgs,
-        _input: Tagged<Value>,
+        _input: Value,
     ) -> Result<OutputStream, ShellError> {
-        call_info.process(&raw_args.shell_manager, mkdir)?.run()
+        call_info
+            .process(&raw_args.shell_manager, raw_args.ctrl_c.clone(), mkdir)?
+            .run()
     }
 }
 

crates/nu-cli/src/commands/mv.rs

@@ -1,8 +1,9 @@
 use crate::commands::command::RunnablePerItemContext;
-use crate::errors::ShellError;
-use crate::parser::hir::SyntaxShape;
-use crate::parser::registry::{CommandRegistry, Signature};
+use crate::context::CommandRegistry;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CallInfo, Signature, SyntaxShape, Value};
+use nu_source::Tagged;
 use std::path::PathBuf;
 
 pub struct Move;
@@ -20,9 +21,16 @@ impl PerItemCommand for Move {
 
     fn signature(&self) -> Signature {
         Signature::build("mv")
-            .required("source", SyntaxShape::Pattern)
-            .required("destination", SyntaxShape::Path)
-            .named("file", SyntaxShape::Any)
+            .required(
+                "source",
+                SyntaxShape::Pattern,
+                "the location to move files/directories from",
+            )
+            .required(
+                "destination",
+                SyntaxShape::Path,
+                "the location to move files/directories to",
+            )
     }
 
     fn usage(&self) -> &str {
@@ -34,9 +42,11 @@ impl PerItemCommand for Move {
         call_info: &CallInfo,
         _registry: &CommandRegistry,
         raw_args: &RawCommandArgs,
-        _input: Tagged<Value>,
+        _input: Value,
     ) -> Result<OutputStream, ShellError> {
-        call_info.process(&raw_args.shell_manager, mv)?.run()
+        call_info
+            .process(&raw_args.shell_manager, raw_args.ctrl_c.clone(), mv)?
+            .run()
     }
 }
 

crates/nu-cli/src/commands/next.rs

@@ -1,7 +1,7 @@
-use crate::commands::command::CommandAction;
 use crate::commands::WholeStreamCommand;
-use crate::errors::ShellError;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CommandAction, ReturnSuccess, Signature};
 
 pub struct Next;
 

crates/nu-cli/src/commands/nth.rs

@@ -0,0 +1,76 @@
+use crate::commands::WholeStreamCommand;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{ReturnSuccess, Signature, SyntaxShape};
+use nu_source::Tagged;
+
+#[derive(Deserialize)]
+struct NthArgs {
+    row_number: Tagged<u64>,
+    rest: Vec<Tagged<u64>>,
+}
+
+pub struct Nth;
+
+impl WholeStreamCommand for Nth {
+    fn name(&self) -> &str {
+        "nth"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("nth")
+            .required(
+                "row number",
+                SyntaxShape::Any,
+                "the number of the row to return",
+            )
+            .rest(SyntaxShape::Any, "Optionally return more rows")
+    }
+
+    fn usage(&self) -> &str {
+        "Return only the selected rows"
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, nth)?.run()
+    }
+}
+
+fn nth(
+    NthArgs {
+        row_number,
+        rest: and_rows,
+    }: NthArgs,
+    RunnableContext { input, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let stream = input
+        .values
+        .enumerate()
+        .map(move |(idx, item)| {
+            let row_number = vec![row_number.clone()];
+
+            let row_numbers = vec![&row_number, &and_rows]
+                .into_iter()
+                .flatten()
+                .collect::<Vec<&Tagged<u64>>>();
+
+            let mut result = VecDeque::new();
+
+            if row_numbers
+                .iter()
+                .any(|requested| requested.item == idx as u64)
+            {
+                result.push_back(ReturnSuccess::value(item));
+            }
+
+            futures::stream::iter(result)
+        })
+        .flatten();
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/open.rs

@@ -1,12 +1,11 @@
-use crate::commands::UnevaluatedCallInfo;
-use crate::context::AnchorLocation;
-use crate::data::meta::Span;
-use crate::data::Value;
-use crate::errors::ShellError;
-use crate::parser::hir::SyntaxShape;
-use crate::parser::registry::Signature;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{
+    CallInfo, CommandAction, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
+};
+use nu_source::{AnchorLocation, Span};
 use std::path::{Path, PathBuf};
+
 pub struct Open;
 
 impl PerItemCommand for Open {
@@ -16,8 +15,16 @@ impl PerItemCommand for Open {
 
     fn signature(&self) -> Signature {
         Signature::build(self.name())
-            .required("path", SyntaxShape::Path)
-            .switch("raw")
+            .required(
+                "path",
+                SyntaxShape::Path,
+                "the file path to load values from",
+            )
+            .switch(
+                "raw",
+                "load content as a string instead of a table",
+                Some('r'),
+            )
     }
 
     fn usage(&self) -> &str {
@@ -27,38 +34,31 @@ impl PerItemCommand for Open {
     fn run(
         &self,
         call_info: &CallInfo,
-        registry: &CommandRegistry,
+        _registry: &CommandRegistry,
         raw_args: &RawCommandArgs,
-        _input: Tagged<Value>,
+        _input: Value,
     ) -> Result<OutputStream, ShellError> {
-        run(call_info, registry, raw_args)
+        run(call_info, raw_args)
     }
 }
 
-fn run(
-    call_info: &CallInfo,
-    registry: &CommandRegistry,
-    raw_args: &RawCommandArgs,
-) -> Result<OutputStream, ShellError> {
+fn run(call_info: &CallInfo, raw_args: &RawCommandArgs) -> Result<OutputStream, ShellError> {
     let shell_manager = &raw_args.shell_manager;
     let cwd = PathBuf::from(shell_manager.path());
-    let full_path = PathBuf::from(cwd);
+    let full_path = cwd;
 
-    let path = match call_info.args.nth(0).ok_or_else(|| {
+    let path = call_info.args.nth(0).ok_or_else(|| {
         ShellError::labeled_error(
             "No file or directory specified",
             "for command",
             &call_info.name_tag,
         )
-    })? {
-        file => file,
-    };
+    })?;
+
     let path_buf = path.as_path()?;
     let path_str = path_buf.display().to_string();
     let path_span = path.tag.span;
     let has_raw = call_info.args.has("raw");
-    let registry = registry.clone();
-    let raw_args = raw_args.clone();
 
     let stream = async_stream! {
 
@@ -68,7 +68,7 @@ fn run(
             yield Err(e);
             return;
         }
-        let (file_extension, contents, contents_tag) = result.unwrap();
+        let (file_extension, contents, contents_tag) = result?;
 
         let file_extension = if has_raw {
             None
@@ -78,43 +78,10 @@ fn run(
             file_extension.or(path_str.split('.').last().map(String::from))
         };
 
-        let tagged_contents = contents.tagged(&contents_tag);
+        let tagged_contents = contents.into_value(&contents_tag);
 
         if let Some(extension) = file_extension {
-            let command_name = format!("from-{}", extension);
-            if let Some(converter) = registry.get_command(&command_name) {
-                let new_args = RawCommandArgs {
-                    host: raw_args.host,
-                    ctrl_c: raw_args.ctrl_c,
-                    shell_manager: raw_args.shell_manager,
-                    call_info: UnevaluatedCallInfo {
-                        args: crate::parser::hir::Call {
-                            head: raw_args.call_info.args.head,
-                            positional: None,
-                            named: None
-                        },
-                        source: raw_args.call_info.source,
-                        name_tag: raw_args.call_info.name_tag,
-                    }
-                };
-                let mut result = converter.run(new_args.with_input(vec![tagged_contents]), &registry, false);
-                let result_vec: Vec<Result<ReturnSuccess, ShellError>> = result.drain_vec().await;
-                for res in result_vec {
-                    match res {
-                        Ok(ReturnSuccess::Value(Tagged { item: Value::Table(list), ..})) => {
-                            for l in list {
-                                yield Ok(ReturnSuccess::Value(l));
-                            }
-                        }
-                        Ok(ReturnSuccess::Value(Tagged { item, .. })) => {
-                            yield Ok(ReturnSuccess::Value(Tagged { item, tag: contents_tag.clone() }));
-                        }
-                        x => yield x,
-                    }
-                }
-            } else {
-                yield ReturnSuccess::value(tagged_contents);
-            }
+            yield Ok(ReturnSuccess::Action(CommandAction::AutoConvert(tagged_contents, extension)))
         } else {
             yield ReturnSuccess::value(tagged_contents);
         }
@@ -127,7 +94,7 @@ pub async fn fetch(
     cwd: &PathBuf,
     location: &str,
     span: Span,
-) -> Result<(Option<String>, Value, Tag), ShellError> {
+) -> Result<(Option<String>, UntaggedValue, Tag), ShellError> {
     let mut cwd = cwd.clone();
 
     cwd.push(Path::new(location));
@@ -137,7 +104,7 @@ pub async fn fetch(
                 Ok(s) => Ok((
                     cwd.extension()
                         .map(|name| name.to_string_lossy().to_string()),
-                    Value::string(s),
+                    UntaggedValue::string(s),
                     Tag {
                         span,
                         anchor: Some(AnchorLocation::File(cwd.to_string_lossy().to_string())),
@@ -155,7 +122,7 @@ pub async fn fetch(
                                     Ok(s) => Ok((
                                         cwd.extension()
                                             .map(|name| name.to_string_lossy().to_string()),
-                                        Value::string(s),
+                                        UntaggedValue::string(s),
                                         Tag {
                                             span,
                                             anchor: Some(AnchorLocation::File(
@@ -165,7 +132,7 @@ pub async fn fetch(
                                     )),
                                     Err(_) => Ok((
                                         None,
-                                        Value::binary(bytes),
+                                        UntaggedValue::binary(bytes),
                                         Tag {
                                             span,
                                             anchor: Some(AnchorLocation::File(
@@ -177,7 +144,7 @@ pub async fn fetch(
                             } else {
                                 Ok((
                                     None,
-                                    Value::binary(bytes),
+                                    UntaggedValue::binary(bytes),
                                     Tag {
                                         span,
                                         anchor: Some(AnchorLocation::File(
@@ -196,7 +163,7 @@ pub async fn fetch(
                                     Ok(s) => Ok((
                                         cwd.extension()
                                             .map(|name| name.to_string_lossy().to_string()),
-                                        Value::string(s),
+                                        UntaggedValue::string(s),
                                         Tag {
                                             span,
                                             anchor: Some(AnchorLocation::File(
@@ -206,7 +173,7 @@ pub async fn fetch(
                                     )),
                                     Err(_) => Ok((
                                         None,
-                                        Value::binary(bytes),
+                                        UntaggedValue::binary(bytes),
                                         Tag {
                                             span,
                                             anchor: Some(AnchorLocation::File(
@@ -218,7 +185,7 @@ pub async fn fetch(
                             } else {
                                 Ok((
                                     None,
-                                    Value::binary(bytes),
+                                    UntaggedValue::binary(bytes),
                                     Tag {
                                         span,
                                         anchor: Some(AnchorLocation::File(
@@ -230,7 +197,7 @@ pub async fn fetch(
                         }
                         _ => Ok((
                             None,
-                            Value::binary(bytes),
+                            UntaggedValue::binary(bytes),
                             Tag {
                                 span,
                                 anchor: Some(AnchorLocation::File(
@@ -241,20 +208,18 @@ pub async fn fetch(
                     }
                 }
             },
-            Err(_) => {
-                return Err(ShellError::labeled_error(
-                    "File could not be opened",
-                    "file not found",
-                    span,
-                ));
-            }
+            Err(_) => Err(ShellError::labeled_error(
+                "File could not be opened",
+                "file not found",
+                span,
+            )),
         }
     } else {
-        return Err(ShellError::labeled_error(
+        Err(ShellError::labeled_error(
             "File could not be opened",
             "file not found",
             span,
-        ));
+        ))
     }
 }
 

crates/nu-cli/src/commands/parse.rs

@@ -0,0 +1,141 @@
+use crate::commands::PerItemCommand;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{
+    CallInfo, ReturnSuccess, Signature, SyntaxShape, TaggedDictBuilder, UntaggedValue, Value,
+};
+
+use nom::{
+    bytes::complete::{tag, take_while},
+    IResult,
+};
+use regex::Regex;
+
+#[derive(Debug)]
+enum ParseCommand {
+    Text(String),
+    Column(String),
+}
+
+fn parse(input: &str) -> IResult<&str, Vec<ParseCommand>> {
+    let mut output = vec![];
+
+    let mut loop_input = input;
+    loop {
+        let (input, before) = take_while(|c| c != '{')(loop_input)?;
+        if !before.is_empty() {
+            output.push(ParseCommand::Text(before.to_string()));
+        }
+        if input != "" {
+            // Look for column as we're now at one
+            let (input, _) = tag("{")(input)?;
+            let (input, column) = take_while(|c| c != '}')(input)?;
+            let (input, _) = tag("}")(input)?;
+
+            output.push(ParseCommand::Column(column.to_string()));
+            loop_input = input;
+        } else {
+            loop_input = input;
+        }
+        if loop_input == "" {
+            break;
+        }
+    }
+
+    Ok((loop_input, output))
+}
+
+fn column_names(commands: &[ParseCommand]) -> Vec<String> {
+    let mut output = vec![];
+
+    for command in commands {
+        if let ParseCommand::Column(c) = command {
+            output.push(c.clone());
+        }
+    }
+
+    output
+}
+
+fn build_regex(commands: &[ParseCommand]) -> String {
+    let mut output = String::new();
+
+    for command in commands {
+        match command {
+            ParseCommand::Text(s) => {
+                output.push_str(&s.replace("(", "\\("));
+            }
+            ParseCommand::Column(_) => {
+                output.push_str("(.*)");
+            }
+        }
+    }
+
+    output
+}
+pub struct Parse;
+
+impl PerItemCommand for Parse {
+    fn name(&self) -> &str {
+        "parse"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("parse").required(
+            "pattern",
+            SyntaxShape::Any,
+            "the pattern to match. Eg) \"{foo}: {bar}\"",
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Parse columns from string data using a simple pattern."
+    }
+
+    fn run(
+        &self,
+        call_info: &CallInfo,
+        _registry: &CommandRegistry,
+        _raw_args: &RawCommandArgs,
+        value: Value,
+    ) -> Result<OutputStream, ShellError> {
+        //let value_tag = value.tag();
+        let pattern = call_info.args.expect_nth(0)?.as_string()?;
+
+        let parse_pattern = parse(&pattern).map_err(|_| {
+            ShellError::labeled_error(
+                "Could not create parse pattern",
+                "could not create parse pattern",
+                &value.tag,
+            )
+        })?;
+        let parse_regex = build_regex(&parse_pattern.1);
+
+        let column_names = column_names(&parse_pattern.1);
+        let regex = Regex::new(&parse_regex).map_err(|_| {
+            ShellError::labeled_error("Could not parse regex", "could not parse regex", &value.tag)
+        })?;
+
+        let output = if let Ok(s) = value.as_string() {
+            let mut results = vec![];
+            for cap in regex.captures_iter(&s) {
+                let mut dict = TaggedDictBuilder::new(value.tag());
+
+                for (idx, column_name) in column_names.iter().enumerate() {
+                    dict.insert_untagged(
+                        column_name,
+                        UntaggedValue::string(&cap[idx + 1].to_string()),
+                    );
+                }
+
+                results.push(ReturnSuccess::value(dict.into_value()));
+            }
+
+            VecDeque::from(results)
+        } else {
+            VecDeque::new()
+        };
+        Ok(output.into())
+    }
+}

crates/nu-cli/src/commands/pick.rs

@@ -0,0 +1,167 @@
+use crate::commands::WholeStreamCommand;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use futures_util::pin_mut;
+use nu_errors::ShellError;
+use nu_protocol::{
+    ColumnPath, PathMember, Primitive, ReturnSuccess, ReturnValue, Signature, SyntaxShape,
+    TaggedDictBuilder, UnspannedPathMember, UntaggedValue, Value,
+};
+use nu_source::span_for_spanned_list;
+use nu_value_ext::{as_string, get_data_by_column_path};
+
+#[derive(Deserialize)]
+struct PickArgs {
+    rest: Vec<ColumnPath>,
+}
+
+pub struct Pick;
+
+impl WholeStreamCommand for Pick {
+    fn name(&self) -> &str {
+        "pick"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pick").rest(
+            SyntaxShape::ColumnPath,
+            "the columns to select from the table",
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Down-select table to only these columns."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, pick)?.run()
+    }
+}
+
+fn pick(
+    PickArgs { rest: mut fields }: PickArgs,
+    RunnableContext { input, name, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    if fields.is_empty() {
+        return Err(ShellError::labeled_error(
+            "Pick requires columns to pick",
+            "needs parameter",
+            name,
+        ));
+    }
+
+    let member = fields.remove(0);
+    let member = vec![member];
+
+    let column_paths = vec![&member, &fields]
+        .into_iter()
+        .flatten()
+        .cloned()
+        .collect::<Vec<ColumnPath>>();
+
+    let stream = async_stream! {
+        let values = input.values;
+        pin_mut!(values);
+
+        let mut empty = true;
+        let mut bring_back: indexmap::IndexMap<String, Vec<Value>> = indexmap::IndexMap::new();
+
+        while let Some(value) = values.next().await {
+            for path in &column_paths {
+                let path_members_span = span_for_spanned_list(path.members().iter().map(|p| p.span));
+
+                let fetcher = get_data_by_column_path(&value, &path, Box::new(move |(obj_source, path_member_tried, error)| {
+                    if let PathMember { unspanned: UnspannedPathMember::String(column), .. } = path_member_tried {
+                        return ShellError::labeled_error_with_secondary(
+                        "No data to fetch.",
+                        format!("Couldn't pick column \"{}\"", column),
+                        path_member_tried.span,
+                        format!("How about exploring it with \"get\"? Check the input is appropriate originating from here"),
+                        obj_source.tag.span)
+                    }
+
+                    error
+                }));
+
+
+                let field = path.clone();
+                let key = as_string(&UntaggedValue::Primitive(Primitive::ColumnPath(field.clone())).into_untagged_value())?;
+
+                match fetcher {
+                    Ok(results) => {
+                        match results.value {
+                            UntaggedValue::Table(records) => {
+                                for x in records {
+                                    let mut out = TaggedDictBuilder::new(name.clone());
+                                    out.insert_untagged(&key, x.value.clone());
+                                    let group = bring_back.entry(key.clone()).or_insert(vec![]);
+                                    group.push(out.into_value());
+                                }
+                            },
+                            x => {
+                                let mut out = TaggedDictBuilder::new(name.clone());
+                                out.insert_untagged(&key, x.clone());
+                                let group = bring_back.entry(key.clone()).or_insert(vec![]);
+                                group.push(out.into_value());
+                            }
+
+                        }
+                    }
+                    Err(reason) => {
+                        // At the moment, we can't add switches, named flags
+                        // and the like while already using .rest since it
+                        // breaks the parser.
+                        //
+                        // We allow flexibility for now and skip the error
+                        // if a given column isn't present.
+                        let strict: Option<bool> = None;
+
+                        if strict.is_some() {
+                            yield Err(reason);
+                            return;
+                        }
+
+                        bring_back.entry(key.clone()).or_insert(vec![]);
+                    }
+                }
+            }
+        }
+
+        let mut max = 0;
+
+        if let Some(max_column) = bring_back.values().max() {
+            max = max_column.len();
+        }
+
+        let keys = bring_back.keys().map(|x| x.clone()).collect::<Vec<String>>();
+
+        for mut current in 0..max  {
+            let mut out = TaggedDictBuilder::new(name.clone());
+
+            for k in &keys {
+                let nothing = UntaggedValue::Primitive(Primitive::Nothing).into_untagged_value();
+                let subsets = bring_back.get(k);
+
+                match subsets {
+                    Some(set) => {
+                        match set.get(current) {
+                            Some(row) => out.insert_untagged(k, row.get_data(k).borrow().clone()),
+                            None => out.insert_untagged(k, nothing.clone()),
+                        }
+                    }
+                    None => out.insert_untagged(k, nothing.clone()),
+                }
+            }
+
+            yield ReturnSuccess::value(out.into_value());
+        }
+    };
+
+    let stream: BoxStream<'static, ReturnValue> = stream.boxed();
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/pivot.rs

@@ -1,7 +1,11 @@
 use crate::commands::WholeStreamCommand;
-use crate::errors::ShellError;
 use crate::prelude::*;
-use crate::TaggedDictBuilder;
+use nu_errors::ShellError;
+use nu_protocol::{
+    merge_descriptors, ReturnSuccess, Signature, SyntaxShape, TaggedDictBuilder, UntaggedValue,
+};
+use nu_source::{SpannedItem, Tagged};
+use nu_value_ext::get_data_by_key;
 
 pub struct Pivot;
 
@@ -21,9 +25,20 @@ impl WholeStreamCommand for Pivot {
 
     fn signature(&self) -> Signature {
         Signature::build("pivot")
-            .switch("header-row")
-            .switch("ignore-titles")
-            .rest(SyntaxShape::String)
+            .switch(
+                "header-row",
+                "treat the first row as column names",
+                Some('r'),
+            )
+            .switch(
+                "ignore-titles",
+                "don't pivot the column names into values",
+                Some('i'),
+            )
+            .rest(
+                SyntaxShape::String,
+                "the names to give columns once pivoted",
+            )
     }
 
     fn usage(&self) -> &str {
@@ -39,25 +54,13 @@ impl WholeStreamCommand for Pivot {
     }
 }
 
-fn merge_descriptors(values: &[Tagged<Value>]) -> Vec<String> {
-    let mut ret = vec![];
-    for value in values {
-        for desc in value.data_descriptors() {
-            if !ret.contains(&desc) {
-                ret.push(desc);
-            }
-        }
-    }
-    ret
-}
-
 pub fn pivot(args: PivotArgs, context: RunnableContext) -> Result<OutputStream, ShellError> {
     let stream = async_stream! {
         let input = context.input.into_vec().await;
 
         let descs = merge_descriptors(&input);
 
-        let mut headers = vec![];
+        let mut headers: Vec<String> = vec![];
 
         if args.rest.len() > 0 && args.header_row {
             yield Err(ShellError::labeled_error("Can not provide header names and use header row", "using header row", context.name));
@@ -67,10 +70,10 @@ pub fn pivot(args: PivotArgs, context: RunnableContext) -> Result<OutputStream,
         if args.header_row {
             for i in input.clone() {
                 if let Some(desc) = descs.get(0) {
-                    match i.get_data_by_key(&desc) {
+                    match get_data_by_key(&i, desc[..].spanned_unknown()) {
                         Some(x) => {
                             if let Ok(s) = x.as_string() {
-                                headers.push(s);
+                                headers.push(s.to_string());
                             } else {
                                 yield Err(ShellError::labeled_error("Header row needs string headers", "used non-string headers", context.name));
                                 return;
@@ -87,7 +90,7 @@ pub fn pivot(args: PivotArgs, context: RunnableContext) -> Result<OutputStream,
                 }
             }
         } else {
-            for i in 0..input.len()+1 {
+            for i in 0..=input.len() {
                 if let Some(name) = args.rest.get(i) {
                     headers.push(name.to_string())
                 } else {
@@ -107,23 +110,23 @@ pub fn pivot(args: PivotArgs, context: RunnableContext) -> Result<OutputStream,
             let mut dict = TaggedDictBuilder::new(&context.name);
 
             if !args.ignore_titles && !args.header_row {
-                dict.insert(headers[column_num].clone(), Value::string(desc.clone()));
+                dict.insert_untagged(headers[column_num].clone(), UntaggedValue::string(desc.clone()));
                 column_num += 1
             }
 
             for i in input.clone() {
-                match i.get_data_by_key(&desc) {
+                match get_data_by_key(&i, desc[..].spanned_unknown()) {
                     Some(x) => {
-                        dict.insert_tagged(headers[column_num].clone(), x.clone());
+                        dict.insert_value(headers[column_num].clone(), x.clone());
                     }
                     _ => {
-                        dict.insert(headers[column_num].clone(), Value::nothing());
+                        dict.insert_untagged(headers[column_num].clone(), UntaggedValue::nothing());
                     }
                 }
                 column_num += 1;
             }
 
-            yield ReturnSuccess::value(dict.into_tagged_value());
+            yield ReturnSuccess::value(dict.into_value());
         }
 
 

crates/nu-cli/src/commands/plugin.rs

@@ -1,9 +1,9 @@
 use crate::commands::WholeStreamCommand;
-use crate::errors::ShellError;
-use crate::parser::registry;
 use crate::prelude::*;
 use derive_new::new;
 use log::trace;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, ReturnValue, Scope, Signature, UntaggedValue, Value};
 use serde::{self, Deserialize, Serialize};
 use std::io::prelude::*;
 use std::io::BufReader;
@@ -39,7 +39,7 @@ pub enum NuResult {
 pub struct PluginCommand {
     name: String,
     path: String,
-    config: registry::Signature,
+    config: Signature,
 }
 
 impl WholeStreamCommand for PluginCommand {
@@ -47,7 +47,7 @@ impl WholeStreamCommand for PluginCommand {
         &self.name
     }
 
-    fn signature(&self) -> registry::Signature {
+    fn signature(&self) -> Signature {
         self.config.clone()
     }
 
@@ -71,7 +71,10 @@ pub fn filter_plugin(
 ) -> Result<OutputStream, ShellError> {
     trace!("filter_plugin :: {}", path);
 
-    let args = args.evaluate_once(registry)?;
+    let args = args.evaluate_once_with_scope(
+        registry,
+        &Scope::it_value(UntaggedValue::string("$it").into_untagged_value()),
+    )?;
 
     let mut child = std::process::Command::new(path)
         .stdin(std::process::Stdio::piped())
@@ -79,11 +82,13 @@ pub fn filter_plugin(
         .spawn()
         .expect("Failed to spawn child process");
 
-    let mut bos: VecDeque<Tagged<Value>> = VecDeque::new();
-    bos.push_back(Value::Primitive(Primitive::BeginningOfStream).tagged_unknown());
+    let mut bos: VecDeque<Value> = VecDeque::new();
+    bos.push_back(UntaggedValue::Primitive(Primitive::BeginningOfStream).into_untagged_value());
+    let bos = futures::stream::iter(bos);
 
-    let mut eos: VecDeque<Tagged<Value>> = VecDeque::new();
-    eos.push_back(Value::Primitive(Primitive::EndOfStream).tagged_unknown());
+    let mut eos: VecDeque<Value> = VecDeque::new();
+    eos.push_back(UntaggedValue::Primitive(Primitive::EndOfStream).into_untagged_value());
+    let eos = futures::stream::iter(eos);
 
     let call_info = args.call_info.clone();
 
@@ -93,8 +98,8 @@ pub fn filter_plugin(
         .chain(args.input.values)
         .chain(eos)
         .map(move |v| match v {
-            Tagged {
-                item: Value::Primitive(Primitive::BeginningOfStream),
+            Value {
+                value: UntaggedValue::Primitive(Primitive::BeginningOfStream),
                 ..
             } => {
                 let stdin = child.stdin.as_mut().expect("Failed to open stdin");
@@ -103,14 +108,26 @@ pub fn filter_plugin(
                 let mut reader = BufReader::new(stdout);
 
                 let request = JsonRpc::new("begin_filter", call_info.clone());
-                let request_raw = serde_json::to_string(&request).unwrap();
-                match stdin.write(format!("{}\n", request_raw).as_bytes()) {
-                    Ok(_) => {}
-                    Err(err) => {
+                let request_raw = serde_json::to_string(&request);
+
+                match request_raw {
+                    Err(_) => {
                         let mut result = VecDeque::new();
-                        result.push_back(Err(ShellError::unexpected(format!("{}", err))));
+                        result.push_back(Err(ShellError::labeled_error(
+                            "Could not load json from plugin",
+                            "could not load json from plugin",
+                            &call_info.name_tag,
+                        )));
                         return result;
                     }
+                    Ok(request_raw) => match stdin.write(format!("{}\n", request_raw).as_bytes()) {
+                        Ok(_) => {}
+                        Err(err) => {
+                            let mut result = VecDeque::new();
+                            result.push_back(Err(ShellError::unexpected(format!("{}", err))));
+                            return result;
+                        }
+                    },
                 }
 
                 let mut input = String::new();
@@ -146,8 +163,8 @@ pub fn filter_plugin(
                     }
                 }
             }
-            Tagged {
-                item: Value::Primitive(Primitive::EndOfStream),
+            Value {
+                value: UntaggedValue::Primitive(Primitive::EndOfStream),
                 ..
             } => {
                 let stdin = child.stdin.as_mut().expect("Failed to open stdin");
@@ -176,8 +193,20 @@ pub fn filter_plugin(
                                 Ok(params) => {
                                     let request: JsonRpc<std::vec::Vec<Value>> =
                                         JsonRpc::new("quit", vec![]);
-                                    let request_raw = serde_json::to_string(&request).unwrap();
-                                    let _ = stdin.write(format!("{}\n", request_raw).as_bytes()); // TODO: Handle error
+                                    let request_raw = serde_json::to_string(&request);
+                                    match request_raw {
+                                        Ok(request_raw) => {
+                                            let _ = stdin.write(format!("{}\n", request_raw).as_bytes()); // TODO: Handle error
+                                        }
+                                        Err(e) => {
+                                            let mut result = VecDeque::new();
+                                            result.push_back(Err(ShellError::untagged_runtime_error(format!(
+                                                "Error while processing begin_filter response: {:?} {}",
+                                                e, input
+                                            ))));
+                                            return result;
+                                        }
+                                    }
 
                                     params
                                 }
@@ -218,8 +247,20 @@ pub fn filter_plugin(
                 let mut reader = BufReader::new(stdout);
 
                 let request = JsonRpc::new("filter", v);
-                let request_raw = serde_json::to_string(&request).unwrap();
-                let _ = stdin.write(format!("{}\n", request_raw).as_bytes()); // TODO: Handle error
+                let request_raw = serde_json::to_string(&request);
+                match request_raw {
+                    Ok(request_raw) => {
+                        let _ = stdin.write(format!("{}\n", request_raw).as_bytes()); // TODO: Handle error
+                    }
+                    Err(e) => {
+                        let mut result = VecDeque::new();
+                        result.push_back(Err(ShellError::untagged_runtime_error(format!(
+                            "Error while processing filter response: {:?}",
+                            e
+                        ))));
+                        return result;
+                    }
+                }
 
                 let mut input = String::new();
                 match reader.read_line(&mut input) {
@@ -237,7 +278,7 @@ pub fn filter_plugin(
                             Err(e) => {
                                 let mut result = VecDeque::new();
                                 result.push_back(Err(ShellError::untagged_runtime_error(format!(
-                                    "Error while processing filter response: {:?} {}",
+                                    "Error while processing filter response: {:?}\n== input ==\n{}",
                                     e, input
                                 ))));
                                 result
@@ -255,6 +296,7 @@ pub fn filter_plugin(
                 }
             }
         })
+        .map(futures::stream::iter) // convert to a stream
         .flatten();
 
     Ok(stream.to_output_stream())
@@ -264,7 +306,7 @@ pub fn filter_plugin(
 pub struct PluginSink {
     name: String,
     path: String,
-    config: registry::Signature,
+    config: Signature,
 }
 
 impl WholeStreamCommand for PluginSink {
@@ -272,7 +314,7 @@ impl WholeStreamCommand for PluginSink {
         &self.name
     }
 
-    fn signature(&self) -> registry::Signature {
+    fn signature(&self) -> Signature {
         self.config.clone()
     }
 
@@ -298,24 +340,34 @@ pub fn sink_plugin(
     let call_info = args.call_info.clone();
 
     let stream = async_stream! {
-        let input: Vec<Tagged<Value>> = args.input.values.collect().await;
+        let input: Vec<Value> = args.input.values.collect().await;
 
         let request = JsonRpc::new("sink", (call_info.clone(), input));
-        let request_raw = serde_json::to_string(&request).unwrap();
-        let mut tmpfile = tempfile::NamedTempFile::new().unwrap();
-        let _ = writeln!(tmpfile, "{}", request_raw);
-        let _ = tmpfile.flush();
+        let request_raw = serde_json::to_string(&request);
+        if let Ok(request_raw) = request_raw {
+            if let Ok(mut tmpfile) = tempfile::NamedTempFile::new() {
+                let _ = writeln!(tmpfile, "{}", request_raw);
+                let _ = tmpfile.flush();
 
-        let mut child = std::process::Command::new(path)
-            .arg(tmpfile.path())
-            .spawn()
-            .expect("Failed to spawn child process");
+                let mut child = std::process::Command::new(path)
+                    .arg(tmpfile.path())
+                    .spawn();
 
-        let _ = child.wait();
+                if let Ok(mut child) = child {
+                    let _ = child.wait();
 
-        // Needed for async_stream to type check
-        if false {
-            yield ReturnSuccess::value(Value::nothing().tagged_unknown());
+                    // Needed for async_stream to type check
+                    if false {
+                        yield ReturnSuccess::value(UntaggedValue::nothing().into_untagged_value());
+                    }
+                } else {
+                    yield Err(ShellError::untagged_runtime_error("Could not create process for sink command"));
+                }
+            } else {
+                yield Err(ShellError::untagged_runtime_error("Could not open file to send sink command message"));
+            }
+        } else {
+            yield Err(ShellError::untagged_runtime_error("Could not create message to sink command"));
         }
     };
     Ok(OutputStream::new(stream))

crates/nu-cli/src/commands/prepend.rs

@@ -0,0 +1,47 @@
+use crate::commands::WholeStreamCommand;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Signature, SyntaxShape, Value};
+
+#[derive(Deserialize)]
+struct PrependArgs {
+    row: Value,
+}
+
+pub struct Prepend;
+
+impl WholeStreamCommand for Prepend {
+    fn name(&self) -> &str {
+        "prepend"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("prepend").required(
+            "row value",
+            SyntaxShape::Any,
+            "the value of the row to prepend to the table",
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Prepend the given row to the front of the table"
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, prepend)?.run()
+    }
+}
+
+fn prepend(
+    PrependArgs { row }: PrependArgs,
+    RunnableContext { input, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let prepend = futures::stream::iter(vec![row]);
+
+    Ok(OutputStream::from_input(prepend.chain(input.values)))
+}

crates/nu-cli/src/commands/prev.rs

@@ -1,6 +1,6 @@
-use crate::commands::command::CommandAction;
-use crate::errors::ShellError;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CommandAction, ReturnSuccess, Signature};
 
 use crate::commands::WholeStreamCommand;
 

crates/nu-cli/src/commands/pwd.rs

@@ -1,11 +1,11 @@
 use crate::commands::WholeStreamCommand;
-use crate::errors::ShellError;
-use crate::parser::registry::Signature;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::Signature;
 
-pub struct PWD;
+pub struct Pwd;
 
-impl WholeStreamCommand for PWD {
+impl WholeStreamCommand for Pwd {
     fn name(&self) -> &str {
         "pwd"
     }

crates/nu-cli/src/commands/range.rs

@@ -0,0 +1,56 @@
+use crate::commands::WholeStreamCommand;
+use crate::context::CommandRegistry;
+use crate::deserializer::NumericRange;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Signature, SyntaxShape};
+use nu_source::Tagged;
+
+#[derive(Deserialize)]
+struct RangeArgs {
+    area: Tagged<NumericRange>,
+}
+
+pub struct Range;
+
+impl WholeStreamCommand for Range {
+    fn name(&self) -> &str {
+        "range"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("range").required(
+            "rows ",
+            SyntaxShape::Range,
+            "range of rows to return: Eg) 4..7 (=> from 4 to 7)",
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Return only the selected rows"
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, range)?.run()
+    }
+}
+
+fn range(
+    RangeArgs { area }: RangeArgs,
+    RunnableContext { input, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let range = area.item;
+    let (from, _) = range.from;
+    let (to, _) = range.to;
+
+    let from = *from as usize;
+    let to = *to as usize;
+
+    Ok(OutputStream::from_input(
+        input.values.skip(from).take(to - from + 1),
+    ))
+}

crates/nu-cli/src/commands/reduce_by.rs

@@ -0,0 +1,72 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use crate::utils::data_processing::reduce;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_source::Tagged;
+use num_traits::cast::ToPrimitive;
+
+pub struct ReduceBy;
+
+#[derive(Deserialize)]
+pub struct ReduceByArgs {
+    reduce_with: Option<Tagged<String>>,
+}
+
+impl WholeStreamCommand for ReduceBy {
+    fn name(&self) -> &str {
+        "reduce-by"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("reduce-by").named(
+            "reduce_with",
+            SyntaxShape::String,
+            "the command to reduce by with",
+            Some('w'),
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Creates a new table with the data from the tables rows reduced by the command given."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, reduce_by)?.run()
+    }
+}
+
+pub fn reduce_by(
+    ReduceByArgs { reduce_with }: ReduceByArgs,
+    RunnableContext { input, name, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let stream = async_stream! {
+        let values: Vec<Value> = input.values.collect().await;
+
+        if values.is_empty() {
+            yield Err(ShellError::labeled_error(
+                    "Expected table from pipeline",
+                    "requires a table input",
+                    name
+                ))
+        } else {
+
+            let reduce_with = if let Some(reducer) = reduce_with {
+                Some(reducer.item().clone())
+            } else {
+                None
+            };
+
+            match reduce(&values[0], reduce_with, name) {
+                Ok(reduced) => yield ReturnSuccess::value(reduced),
+                Err(err) => yield Err(err)
+            }
+        }
+    };
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/reject.rs

@@ -1,7 +1,9 @@
 use crate::commands::WholeStreamCommand;
 use crate::data::base::reject_fields;
-use crate::errors::ShellError;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Signature, SyntaxShape};
+use nu_source::Tagged;
 
 #[derive(Deserialize)]
 pub struct RejectArgs {
@@ -16,7 +18,7 @@ impl WholeStreamCommand for Reject {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("reject").rest(SyntaxShape::Member)
+        Signature::build("reject").rest(SyntaxShape::Member, "the names of columns to remove")
     }
 
     fn usage(&self) -> &str {
@@ -36,7 +38,7 @@ fn reject(
     RejectArgs { rest: fields }: RejectArgs,
     RunnableContext { input, name, .. }: RunnableContext,
 ) -> Result<OutputStream, ShellError> {
-    if fields.len() == 0 {
+    if fields.is_empty() {
         return Err(ShellError::labeled_error(
             "Reject requires fields",
             "needs parameter",
@@ -48,7 +50,7 @@ fn reject(
 
     let stream = input
         .values
-        .map(move |item| reject_fields(&item, &fields, item.tag()).into_tagged_value());
+        .map(move |item| reject_fields(&item, &fields, &item.tag));
 
     Ok(stream.from_input_stream())
 }

crates/nu-cli/src/commands/rename.rs

@@ -0,0 +1,97 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use indexmap::IndexMap;
+use nu_errors::ShellError;
+use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_source::Tagged;
+
+pub struct Rename;
+
+#[derive(Deserialize)]
+pub struct Arguments {
+    column_name: Tagged<String>,
+    rest: Vec<Tagged<String>>,
+}
+
+impl WholeStreamCommand for Rename {
+    fn name(&self) -> &str {
+        "rename"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("rename")
+            .required(
+                "column_name",
+                SyntaxShape::String,
+                "the name of the column to rename for",
+            )
+            .rest(
+                SyntaxShape::Member,
+                "Additional column name(s) to rename for",
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "Creates a new table with columns renamed."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, rename)?.run()
+    }
+}
+
+pub fn rename(
+    Arguments { column_name, rest }: Arguments,
+    RunnableContext { input, name, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let mut new_column_names = vec![vec![column_name]];
+    new_column_names.push(rest);
+
+    let new_column_names = new_column_names.into_iter().flatten().collect::<Vec<_>>();
+
+    let stream = input
+        .values
+        .map(move |item| {
+            let mut result = VecDeque::new();
+
+            if let Value {
+                value: UntaggedValue::Row(row),
+                tag,
+            } = item
+            {
+                let mut renamed_row = IndexMap::new();
+
+                for (idx, (key, value)) in row.entries.iter().enumerate() {
+                    let key = if idx < new_column_names.len() {
+                        &new_column_names[idx].item
+                    } else {
+                        key
+                    };
+
+                    renamed_row.insert(key.clone(), value.clone());
+                }
+
+                let out = UntaggedValue::Row(renamed_row.into()).into_value(tag);
+
+                result.push_back(ReturnSuccess::value(out));
+            } else {
+                result.push_back(ReturnSuccess::value(
+                    UntaggedValue::Error(ShellError::labeled_error(
+                        "no column names available",
+                        "can't rename",
+                        &name,
+                    ))
+                    .into_untagged_value(),
+                ));
+            }
+
+            futures::stream::iter(result)
+        })
+        .flatten();
+
+    Ok(stream.to_output_stream())
+}

crates/nu-cli/src/commands/reverse.rs

@@ -1,7 +1,8 @@
 use crate::commands::WholeStreamCommand;
-use crate::errors::ShellError;
-use crate::parser::CommandRegistry;
+use crate::context::CommandRegistry;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::Signature;
 
 pub struct Reverse;
 
@@ -31,11 +32,11 @@ fn reverse(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStream
     let args = args.evaluate_once(registry)?;
     let (input, _args) = args.parts();
 
-    let output = input.values.collect::<Vec<_>>();
+    let input = input.values.collect::<Vec<_>>();
 
-    let output = output.map(move |mut vec| {
+    let output = input.map(move |mut vec| {
         vec.reverse();
-        vec.into_iter().collect::<VecDeque<_>>()
+        futures::stream::iter(vec)
     });
 
     Ok(output.flatten_stream().from_input_stream())

crates/nu-cli/src/commands/rm.rs

@@ -1,16 +1,18 @@
 use crate::commands::command::RunnablePerItemContext;
-use crate::errors::ShellError;
-use crate::parser::hir::SyntaxShape;
-use crate::parser::registry::{CommandRegistry, Signature};
+use crate::context::CommandRegistry;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{CallInfo, Signature, SyntaxShape, Value};
+use nu_source::Tagged;
 use std::path::PathBuf;
 
 pub struct Remove;
 
 #[derive(Deserialize)]
 pub struct RemoveArgs {
-    pub target: Tagged<PathBuf>,
+    pub rest: Vec<Tagged<PathBuf>>,
     pub recursive: Tagged<bool>,
+    pub trash: Tagged<bool>,
 }
 
 impl PerItemCommand for Remove {
@@ -20,12 +22,17 @@ impl PerItemCommand for Remove {
 
     fn signature(&self) -> Signature {
         Signature::build("rm")
-            .required("path", SyntaxShape::Pattern)
-            .switch("recursive")
+            .switch(
+                "trash",
+                "use the platform's recycle bin instead of permanently deleting",
+                Some('t'),
+            )
+            .switch("recursive", "delete subdirectories recursively", Some('r'))
+            .rest(SyntaxShape::Pattern, "the file path(s) to remove")
     }
 
     fn usage(&self) -> &str {
-        "Remove a file, (for removing directory append '--recursive')"
+        "Remove file(s)"
     }
 
     fn run(
@@ -33,9 +40,11 @@ impl PerItemCommand for Remove {
         call_info: &CallInfo,
         _registry: &CommandRegistry,
         raw_args: &RawCommandArgs,
-        _input: Tagged<Value>,
+        _input: Value,
     ) -> Result<OutputStream, ShellError> {
-        call_info.process(&raw_args.shell_manager, rm)?.run()
+        call_info
+            .process(&raw_args.shell_manager, raw_args.ctrl_c.clone(), rm)?
+            .run()
     }
 }
 

crates/nu-cli/src/commands/save.rs

@@ -1,26 +1,43 @@
 use crate::commands::{UnevaluatedCallInfo, WholeStreamCommand};
-use crate::data::Value;
-use crate::errors::ShellError;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_source::Tagged;
 use std::path::{Path, PathBuf};
 
 pub struct Save;
 
+macro_rules! process_unknown {
+    ($scope:tt, $input:ident, $name_tag:ident) => {{
+        if $input.len() > 0 {
+            match $input[0] {
+                Value {
+                    value: UntaggedValue::Primitive(Primitive::Binary(_)),
+                    ..
+                } => process_binary!($scope, $input, $name_tag),
+                _ => process_string!($scope, $input, $name_tag),
+            }
+        } else {
+            process_string!($scope, $input, $name_tag)
+        }
+    }};
+}
+
 macro_rules! process_string {
     ($scope:tt, $input:ident, $name_tag:ident) => {{
         let mut result_string = String::new();
         for res in $input {
             match res {
-                Tagged {
-                    item: Value::Primitive(Primitive::String(s)),
+                Value {
+                    value: UntaggedValue::Primitive(Primitive::String(s)),
                     ..
                 } => {
                     result_string.push_str(&s);
                 }
                 _ => {
                     break $scope Err(ShellError::labeled_error(
-                        "Save could not successfully save",
-                        "unexpected data during save",
+                        "Save requires string data",
+                        "consider converting data to string (see `help commands`)",
                         $name_tag,
                     ));
                 }
@@ -30,13 +47,39 @@ macro_rules! process_string {
     }};
 }
 
+macro_rules! process_binary {
+    ($scope:tt, $input:ident, $name_tag:ident) => {{
+        let mut result_binary: Vec<u8> = Vec::new();
+        for res in $input {
+            match res {
+                Value {
+                    value: UntaggedValue::Primitive(Primitive::Binary(b)),
+                    ..
+                } => {
+                    for u in b.into_iter() {
+                        result_binary.push(u);
+                    }
+                }
+                _ => {
+                    break $scope Err(ShellError::labeled_error(
+                        "Save could not successfully save",
+                        "unexpected data during binary save",
+                        $name_tag,
+                    ));
+                }
+            }
+        }
+        Ok(result_binary)
+    }};
+}
+
 macro_rules! process_string_return_success {
     ($scope:tt, $result_vec:ident, $name_tag:ident) => {{
         let mut result_string = String::new();
         for res in $result_vec {
             match res {
-                Ok(ReturnSuccess::Value(Tagged {
-                    item: Value::Primitive(Primitive::String(s)),
+                Ok(ReturnSuccess::Value(Value {
+                    value: UntaggedValue::Primitive(Primitive::String(s)),
                     ..
                 })) => {
                     result_string.push_str(&s);
@@ -59,8 +102,8 @@ macro_rules! process_binary_return_success {
         let mut result_binary: Vec<u8> = Vec::new();
         for res in $result_vec {
             match res {
-                Ok(ReturnSuccess::Value(Tagged {
-                    item: Value::Primitive(Primitive::Binary(b)),
+                Ok(ReturnSuccess::Value(Value {
+                    value: UntaggedValue::Primitive(Primitive::Binary(b)),
                     ..
                 })) => {
                     for u in b.into_iter() {
@@ -93,8 +136,12 @@ impl WholeStreamCommand for Save {
 
     fn signature(&self) -> Signature {
         Signature::build("save")
-            .optional("path", SyntaxShape::Path)
-            .switch("raw")
+            .optional("path", SyntaxShape::Path, "the path to save contents to")
+            .switch(
+                "raw",
+                "treat values as-is rather than auto-converting based on file extension",
+                Some('r'),
+            )
     }
 
     fn usage(&self) -> &str {
@@ -130,11 +177,11 @@ fn save(
     let name_tag = name.clone();
 
     let stream = async_stream! {
-        let input: Vec<Tagged<Value>> = input.values.collect().await;
+        let input: Vec<Value> = input.values.collect().await;
         if path.is_none() {
             // If there is no filename, check the metadata for the anchor filename
             if input.len() > 0 {
-                let anchor = input[0].anchor();
+                let anchor = input[0].tag.anchor();
                 match anchor {
                     Some(path) => match path {
                         AnchorLocation::File(file) => {
@@ -142,7 +189,7 @@ fn save(
                         }
                         _ => {
                             yield Err(ShellError::labeled_error(
-                                "Save requires a filepath (1)",
+                                "Save requires a filepath",
                                 "needs path",
                                 name_tag.clone(),
                             ));
@@ -150,7 +197,7 @@ fn save(
                     },
                     None => {
                         yield Err(ShellError::labeled_error(
-                            "Save requires a filepath (2)",
+                            "Save requires a filepath",
                             "needs path",
                             name_tag.clone(),
                         ));
@@ -158,7 +205,7 @@ fn save(
                 }
             } else {
                 yield Err(ShellError::labeled_error(
-                    "Save requires a filepath (3)",
+                    "Save requires a filepath",
                     "needs path",
                     name_tag.clone(),
                 ));
@@ -174,23 +221,24 @@ fn save(
         let content : Result<Vec<u8>, ShellError> = 'scope: loop {
             break if !save_raw {
                 if let Some(extension) = full_path.extension() {
-                    let command_name = format!("to-{}", extension.to_str().unwrap());
+                    let command_name = format!("to-{}", extension.to_string_lossy());
                     if let Some(converter) = registry.get_command(&command_name) {
                         let new_args = RawCommandArgs {
                             host,
                             ctrl_c,
                             shell_manager,
                             call_info: UnevaluatedCallInfo {
-                                args: crate::parser::hir::Call {
+                                args: nu_parser::hir::Call {
                                     head: raw_args.call_info.args.head,
                                     positional: None,
-                                    named: None
+                                    named: None,
+                                    span: Span::unknown()
                                 },
                                 source: raw_args.call_info.source,
                                 name_tag: raw_args.call_info.name_tag,
                             }
                         };
-                        let mut result = converter.run(new_args.with_input(input), &registry, false);
+                        let mut result = converter.run(new_args.with_input(input), &registry);
                         let result_vec: Vec<Result<ReturnSuccess, ShellError>> = result.drain_vec().await;
                         if converter.is_binary() {
                             process_binary_return_success!('scope, result_vec, name_tag)
@@ -198,10 +246,10 @@ fn save(
                             process_string_return_success!('scope, result_vec, name_tag)
                         }
                     } else {
-                        process_string!('scope, input, name_tag)
+                        process_unknown!('scope, input, name_tag)
                     }
                 } else {
-                    process_string!('scope, input, name_tag)
+                    process_unknown!('scope, input, name_tag)
                 }
             } else {
                 Ok(string_from(&input).into_bytes())
@@ -211,9 +259,9 @@ fn save(
         match content {
             Ok(save_data) => match std::fs::write(full_path, save_data) {
                 Ok(o) => o,
-                Err(e) => yield Err(ShellError::labeled_error(e.to_string(), "for command", name)),
+                Err(e) => yield Err(ShellError::labeled_error(e.to_string(), "IO error while saving", name)),
             },
-            Err(e) => yield Err(ShellError::labeled_error(e.to_string(), "for command", name)),
+            Err(e) => yield Err(e),
         }
 
     };
@@ -221,10 +269,10 @@ fn save(
     Ok(OutputStream::new(stream))
 }
 
-fn string_from(input: &Vec<Tagged<Value>>) -> String {
+fn string_from(input: &[Value]) -> String {
     let mut save_data = String::new();
 
-    if input.len() > 0 {
+    if !input.is_empty() {
         let mut first = true;
         for i in input.iter() {
             if !first {

crates/nu-cli/src/commands/shells.rs

@@ -1,7 +1,7 @@
 use crate::commands::WholeStreamCommand;
-use crate::data::TaggedDictBuilder;
-use crate::errors::ShellError;
 use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Signature, TaggedDictBuilder};
 use std::sync::atomic::Ordering;
 
 pub struct Shells;
@@ -32,19 +32,19 @@ fn shells(args: CommandArgs, _registry: &CommandRegistry) -> Result<OutputStream
     let mut shells_out = VecDeque::new();
     let tag = args.call_info.name_tag;
 
-    for (index, shell) in args.shell_manager.shells.lock().unwrap().iter().enumerate() {
+    for (index, shell) in args.shell_manager.shells.lock().iter().enumerate() {
         let mut dict = TaggedDictBuilder::new(&tag);
 
         if index == (*args.shell_manager.current_shell).load(Ordering::SeqCst) {
-            dict.insert(" ", "X".to_string());
+            dict.insert_untagged(" ", "X".to_string());
         } else {
-            dict.insert(" ", " ".to_string());
+            dict.insert_untagged(" ", " ".to_string());
         }
-        dict.insert("name", shell.name());
-        dict.insert("path", shell.path());
+        dict.insert_untagged("name", shell.name());
+        dict.insert_untagged("path", shell.path());
 
-        shells_out.push_back(dict.into_tagged_value());
+        shells_out.push_back(dict.into_value());
     }
 
-    Ok(shells_out.to_output_stream())
+    Ok(shells_out.into())
 }

crates/nu-cli/src/commands/shuffle.rs

@@ -0,0 +1,69 @@
+use crate::commands::WholeStreamCommand;
+use crate::context::CommandRegistry;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{ReturnSuccess, ReturnValue, Signature, SyntaxShape, Value};
+use nu_source::Tagged;
+
+use rand::seq::SliceRandom;
+use rand::thread_rng;
+
+pub struct Shuffle;
+
+#[derive(Deserialize)]
+pub struct Arguments {
+    #[serde(rename = "num")]
+    limit: Option<Tagged<u64>>,
+}
+
+impl WholeStreamCommand for Shuffle {
+    fn name(&self) -> &str {
+        "shuffle"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("shuffle").named(
+            "num",
+            SyntaxShape::Int,
+            "Limit `num` number of rows",
+            Some('n'),
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Shuffle rows randomly."
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, shuffle)?.run()
+    }
+}
+
+fn shuffle(
+    Arguments { limit }: Arguments,
+    RunnableContext { input, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let stream = async_stream! {
+        let mut values: Vec<Value> = input.values.collect().await;
+
+        let out = if let Some(n) = limit {
+            let (shuffled, _) = values.partial_shuffle(&mut thread_rng(), *n as usize);
+            shuffled.to_vec()
+        } else {
+            values.shuffle(&mut thread_rng());
+            values.clone()
+        };
+
+        for val in out.into_iter() {
+            yield ReturnSuccess::value(val);
+        }
+    };
+
+    let stream: BoxStream<'static, ReturnValue> = stream.boxed();
+
+    Ok(stream.to_output_stream())
+}