Update Cargo.lock (#3527)

* Bump to 0.32

* Bump to 0.32

Cargo.toml

@@ -10,7 +10,7 @@ license = "MIT"
 name = "nu"
 readme = "README.md"
 repository = "https://github.com/nushell/nushell"
-version = "0.30.0"
+version = "0.32.0"
 
 [workspace]
 members = ["crates/*/"]
@@ -18,36 +18,36 @@ members = ["crates/*/"]
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-nu-cli = { version = "0.30.0", path = "./crates/nu-cli", default-features = false }
+nu-cli = { version = "0.32.0", path = "./crates/nu-cli", default-features = false }
-nu-command = { version = "0.30.0", path = "./crates/nu-command" }
+nu-command = { version = "0.32.0", path = "./crates/nu-command" }
-nu-data = { version = "0.30.0", path = "./crates/nu-data" }
+nu-data = { version = "0.32.0", path = "./crates/nu-data" }
-nu-engine = { version = "0.30.0", path = "./crates/nu-engine" }
+nu-engine = { version = "0.32.0", path = "./crates/nu-engine" }
-nu-errors = { version = "0.30.0", path = "./crates/nu-errors" }
+nu-errors = { version = "0.32.0", path = "./crates/nu-errors" }
-nu-parser = { version = "0.30.0", path = "./crates/nu-parser" }
+nu-parser = { version = "0.32.0", path = "./crates/nu-parser" }
-nu-plugin = { version = "0.30.0", path = "./crates/nu-plugin" }
+nu-plugin = { version = "0.32.0", path = "./crates/nu-plugin" }
-nu-protocol = { version = "0.30.0", path = "./crates/nu-protocol" }
+nu-protocol = { version = "0.32.0", path = "./crates/nu-protocol" }
-nu-source = { version = "0.30.0", path = "./crates/nu-source" }
+nu-source = { version = "0.32.0", path = "./crates/nu-source" }
-nu-value-ext = { version = "0.30.0", path = "./crates/nu-value-ext" }
+nu-value-ext = { version = "0.32.0", path = "./crates/nu-value-ext" }
 
-nu_plugin_binaryview = { version = "0.30.0", path = "./crates/nu_plugin_binaryview", optional = true }
+nu_plugin_binaryview = { version = "0.32.0", path = "./crates/nu_plugin_binaryview", optional = true }
-nu_plugin_chart = { version = "0.30.0", path = "./crates/nu_plugin_chart", optional = true }
+nu_plugin_chart = { version = "0.32.0", path = "./crates/nu_plugin_chart", optional = true }
-nu_plugin_fetch = { version = "0.30.0", path = "./crates/nu_plugin_fetch", optional = true }
+nu_plugin_fetch = { version = "0.32.0", path = "./crates/nu_plugin_fetch", optional = true }
-nu_plugin_from_bson = { version = "0.30.0", path = "./crates/nu_plugin_from_bson", optional = true }
+nu_plugin_from_bson = { version = "0.32.0", path = "./crates/nu_plugin_from_bson", optional = true }
-nu_plugin_from_sqlite = { version = "0.30.0", path = "./crates/nu_plugin_from_sqlite", optional = true }
+nu_plugin_from_sqlite = { version = "0.32.0", path = "./crates/nu_plugin_from_sqlite", optional = true }
-nu_plugin_inc = { version = "0.30.0", path = "./crates/nu_plugin_inc", optional = true }
+nu_plugin_inc = { version = "0.32.0", path = "./crates/nu_plugin_inc", optional = true }
-nu_plugin_match = { version = "0.30.0", path = "./crates/nu_plugin_match", optional = true }
+nu_plugin_match = { version = "0.32.0", path = "./crates/nu_plugin_match", optional = true }
-nu_plugin_post = { version = "0.30.0", path = "./crates/nu_plugin_post", optional = true }
+nu_plugin_post = { version = "0.32.0", path = "./crates/nu_plugin_post", optional = true }
-nu_plugin_ps = { version = "0.30.0", path = "./crates/nu_plugin_ps", optional = true }
+nu_plugin_ps = { version = "0.32.0", path = "./crates/nu_plugin_ps", optional = true }
-nu_plugin_query_json = { version = "0.30.0", path = "./crates/nu_plugin_query_json", optional = true }
+nu_plugin_query_json = { version = "0.32.0", path = "./crates/nu_plugin_query_json", optional = true }
-nu_plugin_s3 = { version = "0.30.0", path = "./crates/nu_plugin_s3", optional = true }
+nu_plugin_s3 = { version = "0.32.0", path = "./crates/nu_plugin_s3", optional = true }
-nu_plugin_selector = { version = "0.30.0", path = "./crates/nu_plugin_selector", optional = true }
+nu_plugin_selector = { version = "0.32.0", path = "./crates/nu_plugin_selector", optional = true }
-nu_plugin_start = { version = "0.30.0", path = "./crates/nu_plugin_start", optional = true }
+nu_plugin_start = { version = "0.32.0", path = "./crates/nu_plugin_start", optional = true }
-nu_plugin_sys = { version = "0.30.0", path = "./crates/nu_plugin_sys", optional = true }
+nu_plugin_sys = { version = "0.32.0", path = "./crates/nu_plugin_sys", optional = true }
-nu_plugin_textview = { version = "0.30.0", path = "./crates/nu_plugin_textview", optional = true }
+nu_plugin_textview = { version = "0.32.0", path = "./crates/nu_plugin_textview", optional = true }
-nu_plugin_to_bson = { version = "0.30.0", path = "./crates/nu_plugin_to_bson", optional = true }
+nu_plugin_to_bson = { version = "0.32.0", path = "./crates/nu_plugin_to_bson", optional = true }
-nu_plugin_to_sqlite = { version = "0.30.0", path = "./crates/nu_plugin_to_sqlite", optional = true }
+nu_plugin_to_sqlite = { version = "0.32.0", path = "./crates/nu_plugin_to_sqlite", optional = true }
-nu_plugin_tree = { version = "0.30.0", path = "./crates/nu_plugin_tree", optional = true }
+nu_plugin_tree = { version = "0.32.0", path = "./crates/nu_plugin_tree", optional = true }
-nu_plugin_xpath = { version = "0.30.0", path = "./crates/nu_plugin_xpath", optional = true }
+nu_plugin_xpath = { version = "0.32.0", path = "./crates/nu_plugin_xpath", optional = true }
 
 # Required to bootstrap the main binary
 clap = "2.33.3"
@@ -58,7 +58,7 @@ log = "0.4.14"
 pretty_env_logger = "0.4.0"
 
 [dev-dependencies]
-nu-test-support = { version = "0.30.0", path = "./crates/nu-test-support" }
+nu-test-support = { version = "0.32.0", path = "./crates/nu-test-support" }
 dunce = "1.0.1"
 serial_test = "0.5.1"
 hamcrest2 = "0.3.0"
@@ -81,13 +81,7 @@ ptree-support = ["nu-cli/ptree", "nu-command/ptree"]
 rustyline-support = ["nu-cli/rustyline-support", "nu-command/rustyline-support"]
 term-support = ["nu-cli/term", "nu-command/term"]
 uuid-support = ["nu-cli/uuid_crate", "nu-command/uuid_crate"]
-which-support = [
+which-support = ["nu-cli/which", "nu-command/which", "nu-engine/which"]
-    "nu-cli/ichwh",
-    "nu-cli/which",
-    "nu-command/ichwh",
-    "nu-command/which",
-    "nu-engine/which",
-]
 
 default = [
     "nu-cli/shadow-rs",
@@ -160,6 +154,17 @@ zip-support = ["nu-cli/zip", "nu-command/zip"]
 #This is disabled in extra for now
 table-pager = ["nu-command/table-pager"]
 
+#dataframe feature for nushell
+dataframe = [
+    "nu-protocol/dataframe",
+    "nu-command/dataframe",
+    "nu-value-ext/dataframe",
+    "nu-data/dataframe",
+    "nu_plugin_post/dataframe",
+    "nu_plugin_to_bson/dataframe",
+]
+
+
 [profile.release]
 #strip = "symbols" #Couldn't get working +nightly
 codegen-units = 1 #Reduce parallel codegen units

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2019 - 2020 Yehuda Katz, Jonathan Turner
+Copyright (c) 2019 - 2021 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

README.md

@@ -47,7 +47,7 @@ Try it in Gitpod.
 
 Up-to-date installation instructions can be found in the [installation chapter of the book](https://www.nushell.sh/book/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 **latest stable (1.47 or later)** version of the compiler.
+To build Nu, you will need to use the **latest stable (1.51 or later)** version of the compiler.
 
 Required dependencies:
 
@@ -220,7 +220,7 @@ We can pipeline this into a command that gets the contents of one of the columns
  name          │ nu
  readme        │ README.md
  repository    │ https://github.com/nushell/nushell
- version       │ 0.21.0
+ version       │ 0.32.0
 ───────────────┴────────────────────────────────────
 ```
 
@@ -228,7 +228,7 @@ Finally, we can use commands outside of Nu once we have the data we want:
 
 ```shell
 > open Cargo.toml | get package.version
-0.21.0
+0.32.0
 ```
 
 Here we use the variable `$it` to refer to the value being piped to the external command.

crates/nu-ansi-term/Cargo.toml

@@ -9,7 +9,7 @@ description = "Library for ANSI terminal colors and styles (bold, underline)"
 edition = "2018"
 license = "MIT"
 name = "nu-ansi-term"
-version = "0.30.0"
+version = "0.32.0"
 
 [lib]
 doctest = false

crates/nu-cli/Cargo.toml

@@ -5,26 +5,27 @@ description = "CLI for nushell"
 edition = "2018"
 license = "MIT"
 name = "nu-cli"
-version = "0.30.0"
+version = "0.32.0"
 
 [lib]
 doctest = false
 
 [dependencies]
-nu-command = { version = "0.30.0", path = "../nu-command" }
+nu-command = { version = "0.32.0", path = "../nu-command" }
-nu-data = { version = "0.30.0", path = "../nu-data" }
+nu-data = { version = "0.32.0", path = "../nu-data" }
-nu-engine = { version = "0.30.0", path = "../nu-engine" }
+nu-engine = { version = "0.32.0", path = "../nu-engine" }
-nu-errors = { version = "0.30.0", path = "../nu-errors" }
+nu-errors = { version = "0.32.0", path = "../nu-errors" }
-nu-json = { version = "0.30.0", path = "../nu-json" }
+nu-json = { version = "0.32.0", path = "../nu-json" }
-nu-parser = { version = "0.30.0", path = "../nu-parser" }
+nu-parser = { version = "0.32.0", path = "../nu-parser" }
-nu-plugin = { version = "0.30.0", path = "../nu-plugin" }
+nu-plugin = { version = "0.32.0", path = "../nu-plugin" }
-nu-protocol = { version = "0.30.0", path = "../nu-protocol" }
+nu-protocol = { version = "0.32.0", path = "../nu-protocol" }
-nu-source = { version = "0.30.0", path = "../nu-source" }
+nu-source = { version = "0.32.0", path = "../nu-source" }
-nu-stream = { version = "0.30.0", path = "../nu-stream" }
+nu-stream = { version = "0.32.0", path = "../nu-stream" }
-nu-table = { version = "0.30.0", path = "../nu-table" }
+nu-table = { version = "0.32.0", path = "../nu-table" }
-nu-test-support = { version = "0.30.0", path = "../nu-test-support" }
+nu-test-support = { version = "0.32.0", path = "../nu-test-support" }
-nu-value-ext = { version = "0.30.0", path = "../nu-value-ext" }
+nu-value-ext = { version = "0.32.0", path = "../nu-value-ext" }
-nu-ansi-term = { version = "0.30.0", path = "../nu-ansi-term" }
+nu-ansi-term = { version = "0.32.0", path = "../nu-ansi-term" }
+nu-pretty-hex = { version = "0.32.0", path = "../nu-pretty-hex" }
 
 Inflector = "0.11"
 arboard = { version = "1.1.0", optional = true }
@@ -57,7 +58,6 @@ getset = "0.1.1"
 glob = "0.3.0"
 htmlescape = "0.3.1"
 ical = "0.7.0"
-ichwh = { version = "0.3.4", optional = true }
 indexmap = { version = "1.6.1", features = ["serde-1"] }
 itertools = "0.10.0"
 lazy_static = "1.*"
@@ -68,7 +68,6 @@ num-format = { version = "0.4.0", features = ["with-num-bigint"] }
 num-traits = "0.2.14"
 parking_lot = "0.11.1"
 pin-utils = "0.1.0"
-pretty-hex = "0.2.1"
 ptree = { version = "0.3.1", optional = true }
 query_interface = "0.3.5"
 quick-xml = "0.21.0"
@@ -77,7 +76,7 @@ rayon = "1.5.0"
 regex = "1.4.3"
 roxmltree = "0.14.0"
 rust-embed = "5.9.0"
-rustyline = { version = "8.0.0", optional = true }
+rustyline = { version = "8.1.0", optional = true }
 serde = { version = "1.0.123", features = ["derive"] }
 serde_bytes = "0.11.5"
 serde_ini = "0.2.0"
@@ -116,7 +115,7 @@ users = "0.11.0"
 [dependencies.rusqlite]
 features = ["bundled", "blob"]
 optional = true
-version = "0.24.2"
+version = "0.25.3"
 
 [build-dependencies]
 shadow-rs = "0.5"

crates/nu-cli/src/cli.rs

@@ -229,13 +229,7 @@ pub fn cli(context: EvaluationContext, options: Options) -> Result<(), Box<dyn E
                 let prompt_line = prompt.as_string()?;
 
                 context.scope.enter_scope();
-                let (mut prompt_block, err) = nu_parser::parse(&prompt_line, 0, &context.scope);
+                let (prompt_block, err) = nu_parser::parse(&prompt_line, 0, &context.scope);
-
-                if let Some(block) =
-                    std::sync::Arc::<nu_protocol::hir::Block>::get_mut(&mut prompt_block)
-                {
-                    block.set_redirect(ExternalRedirection::Stdout);
-                }
 
                 if err.is_some() {
                     context.scope.exit_scope();
@@ -250,7 +244,12 @@ pub fn cli(context: EvaluationContext, options: Options) -> Result<(), Box<dyn E
                         nu_ansi_term::ansi::RESET
                     )
                 } else {
-                    let run_result = run_block(&prompt_block, &context, InputStream::empty());
+                    let run_result = run_block(
+                        &prompt_block,
+                        &context,
+                        InputStream::empty(),
+                        ExternalRedirection::Stdout,
+                    );
                     context.scope.exit_scope();
 
                     match run_result {
@@ -302,7 +301,9 @@ pub fn cli(context: EvaluationContext, options: Options) -> Result<(), Box<dyn E
             }
         };
 
-        rl.helper_mut().expect("No helper").colored_prompt = colored_prompt;
+        if let Some(helper) = rl.helper_mut() {
+            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 {
@@ -485,7 +486,12 @@ pub fn parse_and_eval(line: &str, ctx: &EvaluationContext) -> Result<String, She
 
     let input_stream = InputStream::empty();
 
-    let result = run_block(&classified_block, ctx, input_stream);
+    let result = run_block(
+        &classified_block,
+        ctx,
+        input_stream,
+        ExternalRedirection::Stdout,
+    );
     ctx.scope.exit_scope();
 
     result?.collect_string(Tag::unknown()).map(|x| x.item)
@@ -509,14 +515,14 @@ fn current_branch() -> String {
 
 #[cfg(test)]
 mod tests {
-    use nu_engine::basic_evaluation_context;
+    use nu_engine::EvaluationContext;
 
     #[quickcheck]
     fn quickcheck_parse(data: String) -> bool {
         let (tokens, err) = nu_parser::lex(&data, 0);
         let (lite_block, err2) = nu_parser::parse_block(tokens);
         if err.is_none() && err2.is_none() {
-            let context = basic_evaluation_context().unwrap();
+            let context = EvaluationContext::basic();
             let _ = nu_parser::classify_block(&lite_block, &context.scope);
         }
         true

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

@@ -6,6 +6,7 @@ use indexmap::set::IndexSet;
 use super::matchers::Matcher;
 use crate::completion::{Completer, CompletionContext, Suggestion};
 use nu_engine::EvaluationContext;
+use nu_test_support::NATIVE_PATH_ENV_VAR;
 
 pub struct CommandCompleter;
 
@@ -121,7 +122,7 @@ fn is_executable(path: &Path) -> bool {
 
 // TODO cache these, but watch for changes to PATH
 fn find_path_executables() -> Option<IndexSet<String>> {
-    let path_var = std::env::var_os("PATH")?;
+    let path_var = std::env::var_os(NATIVE_PATH_ENV_VAR)?;
     let paths: Vec<_> = std::env::split_paths(&path_var).collect();
 
     let mut executables: IndexSet<String> = IndexSet::new();

crates/nu-cli/src/completion/engine.rs

@@ -37,7 +37,7 @@ impl<'s> Flatten<'s> {
                 )
                 .collect(),
             Expression::Command => vec![LocationType::Command.spanned(e.span)],
-            Expression::Path(path) => self.expression(&path.head),
+            Expression::FullColumnPath(path) => self.expression(&path.head),
             Expression::Variable(_, _) => vec![LocationType::Variable.spanned(e.span)],
 
             Expression::Boolean(_)
@@ -384,7 +384,7 @@ mod tests {
         #[test]
         fn completes_incomplete_nested_structure() {
             let registry: VecRegistry = vec![Signature::build("sys")].into();
-            let line = "echo $(sy";
+            let line = "echo (sy";
 
             assert_eq!(
                 completion_location(line, &registry, 8),

crates/nu-cli/src/keybinding.rs

@@ -1,63 +1,42 @@
-use rustyline::{KeyCode, Modifiers};
+use rustyline::{KeyCode as RustyKeyCode, Modifiers};
 use serde::{Deserialize, Serialize};
 
-pub fn convert_keyevent(key_event: KeyEvent) -> rustyline::KeyEvent {
+pub fn convert_keyevent(key_event: KeyCode, modifiers: Option<Modifiers>) -> rustyline::KeyEvent {
     match key_event {
-        KeyEvent::UnknownEscSeq => convert_to_rl_keyevent(rustyline::KeyCode::UnknownEscSeq, None),
+        KeyCode::UnknownEscSeq => convert_to_rl_keyevent(RustyKeyCode::UnknownEscSeq, modifiers),
-        KeyEvent::Backspace => convert_to_rl_keyevent(rustyline::KeyCode::Backspace, None),
+        KeyCode::Backspace => convert_to_rl_keyevent(RustyKeyCode::Backspace, modifiers),
-        KeyEvent::BackTab => convert_to_rl_keyevent(rustyline::KeyCode::BackTab, None),
+        KeyCode::BackTab => convert_to_rl_keyevent(RustyKeyCode::BackTab, modifiers),
-        KeyEvent::BracketedPasteStart => {
+        KeyCode::BracketedPasteStart => {
-            convert_to_rl_keyevent(rustyline::KeyCode::BracketedPasteStart, None)
+            convert_to_rl_keyevent(RustyKeyCode::BracketedPasteStart, modifiers)
         }
-        KeyEvent::BracketedPasteEnd => {
+        KeyCode::BracketedPasteEnd => {
-            convert_to_rl_keyevent(rustyline::KeyCode::BracketedPasteEnd, None)
+            convert_to_rl_keyevent(RustyKeyCode::BracketedPasteEnd, modifiers)
         }
-        KeyEvent::Char(c) => convert_to_rl_keyevent(rustyline::KeyCode::Char(c), None),
+        KeyCode::Char(c) => convert_to_rl_keyevent(RustyKeyCode::Char(c), modifiers),
-        KeyEvent::ControlDown => {
+        KeyCode::Delete => convert_to_rl_keyevent(RustyKeyCode::Delete, modifiers),
-            convert_to_rl_keyevent(rustyline::KeyCode::Down, Some(Modifiers::CTRL))
+        KeyCode::Down => convert_to_rl_keyevent(RustyKeyCode::Down, modifiers),
-        }
+        KeyCode::End => convert_to_rl_keyevent(RustyKeyCode::End, modifiers),
-        KeyEvent::ControlLeft => {
+        KeyCode::Enter => convert_to_rl_keyevent(RustyKeyCode::Enter, modifiers),
-            convert_to_rl_keyevent(rustyline::KeyCode::Left, Some(Modifiers::CTRL))
+        KeyCode::Esc => convert_to_rl_keyevent(RustyKeyCode::Esc, modifiers),
-        }
+        KeyCode::F(u) => convert_to_rl_keyevent(RustyKeyCode::F(u), modifiers),
-        KeyEvent::ControlRight => {
+        KeyCode::Home => convert_to_rl_keyevent(RustyKeyCode::Home, modifiers),
-            convert_to_rl_keyevent(rustyline::KeyCode::Right, Some(Modifiers::CTRL))
+        KeyCode::Insert => convert_to_rl_keyevent(RustyKeyCode::Insert, modifiers),
-        }
+        KeyCode::Left => convert_to_rl_keyevent(RustyKeyCode::Left, modifiers),
-        KeyEvent::ControlUp => {
+        KeyCode::Null => convert_to_rl_keyevent(RustyKeyCode::Null, modifiers),
-            convert_to_rl_keyevent(rustyline::KeyCode::Up, Some(Modifiers::CTRL))
+        KeyCode::PageDown => convert_to_rl_keyevent(RustyKeyCode::PageDown, modifiers),
-        }
+        KeyCode::PageUp => convert_to_rl_keyevent(RustyKeyCode::PageUp, modifiers),
-        KeyEvent::Ctrl(c) => rustyline::KeyEvent::ctrl(c),
+        KeyCode::Right => convert_to_rl_keyevent(RustyKeyCode::Right, modifiers),
-        KeyEvent::Delete => convert_to_rl_keyevent(rustyline::KeyCode::Delete, None),
+        KeyCode::Tab => convert_to_rl_keyevent(RustyKeyCode::Tab, modifiers),
-        KeyEvent::Down => convert_to_rl_keyevent(rustyline::KeyCode::Down, None),
+        KeyCode::Up => convert_to_rl_keyevent(RustyKeyCode::Up, modifiers),
-        KeyEvent::End => convert_to_rl_keyevent(rustyline::KeyCode::End, None),
-        KeyEvent::Enter => convert_to_rl_keyevent(rustyline::KeyCode::Enter, None),
-        KeyEvent::Esc => convert_to_rl_keyevent(rustyline::KeyCode::Esc, None),
-        KeyEvent::F(u) => convert_to_rl_keyevent(rustyline::KeyCode::F(u), None),
-        KeyEvent::Home => convert_to_rl_keyevent(rustyline::KeyCode::Home, None),
-        KeyEvent::Insert => convert_to_rl_keyevent(rustyline::KeyCode::Insert, None),
-        KeyEvent::Left => convert_to_rl_keyevent(rustyline::KeyCode::Left, None),
-        KeyEvent::Meta(c) => rustyline::KeyEvent::new(c, Modifiers::NONE),
-        KeyEvent::Null => convert_to_rl_keyevent(rustyline::KeyCode::Null, None),
-        KeyEvent::PageDown => convert_to_rl_keyevent(rustyline::KeyCode::PageDown, None),
-        KeyEvent::PageUp => convert_to_rl_keyevent(rustyline::KeyCode::PageUp, None),
-        KeyEvent::Right => convert_to_rl_keyevent(rustyline::KeyCode::Right, None),
-        KeyEvent::ShiftDown => {
-            convert_to_rl_keyevent(rustyline::KeyCode::Down, Some(Modifiers::SHIFT))
-        }
-        KeyEvent::ShiftLeft => {
-            convert_to_rl_keyevent(rustyline::KeyCode::Left, Some(Modifiers::SHIFT))
-        }
-        KeyEvent::ShiftRight => {
-            convert_to_rl_keyevent(rustyline::KeyCode::Right, Some(Modifiers::SHIFT))
-        }
-        KeyEvent::ShiftUp => convert_to_rl_keyevent(rustyline::KeyCode::Up, Some(Modifiers::SHIFT)),
-        KeyEvent::Tab => convert_to_rl_keyevent(rustyline::KeyCode::Tab, None),
-        KeyEvent::Up => convert_to_rl_keyevent(rustyline::KeyCode::Up, None),
     }
 }
 
-fn convert_to_rl_keyevent(key_event: KeyCode, modifier: Option<Modifiers>) -> rustyline::KeyEvent {
+fn convert_to_rl_keyevent(
+    key_code: RustyKeyCode,
+    modifier: Option<Modifiers>,
+) -> rustyline::KeyEvent {
     rustyline::KeyEvent {
-        0: key_event,
+        0: key_code,
         1: modifier.unwrap_or(Modifiers::NONE),
     }
 }
@@ -132,12 +111,14 @@ fn convert_cmd(cmd: Cmd) -> rustyline::Cmd {
         Cmd::Complete => rustyline::Cmd::Complete,
         Cmd::CompleteBackward => rustyline::Cmd::CompleteBackward,
         Cmd::CompleteHint => rustyline::Cmd::CompleteHint,
+        Cmd::Dedent(movement) => rustyline::Cmd::Dedent(convert_movement(movement)),
         Cmd::DowncaseWord => rustyline::Cmd::DowncaseWord,
         Cmd::EndOfFile => rustyline::Cmd::EndOfFile,
         Cmd::EndOfHistory => rustyline::Cmd::EndOfHistory,
         Cmd::ForwardSearchHistory => rustyline::Cmd::ForwardSearchHistory,
         Cmd::HistorySearchBackward => rustyline::Cmd::HistorySearchBackward,
         Cmd::HistorySearchForward => rustyline::Cmd::HistorySearchForward,
+        Cmd::Indent(movement) => rustyline::Cmd::Indent(convert_movement(movement)),
         Cmd::Insert { repeat, string } => rustyline::Cmd::Insert(repeat, string),
         Cmd::Interrupt => rustyline::Cmd::Interrupt,
         Cmd::Kill(movement) => rustyline::Cmd::Kill(convert_movement(movement)),
@@ -145,8 +126,11 @@ fn convert_cmd(cmd: Cmd) -> rustyline::Cmd {
         Cmd::LineUpOrPreviousHistory(u) => rustyline::Cmd::LineUpOrPreviousHistory(u),
         Cmd::Move(movement) => rustyline::Cmd::Move(convert_movement(movement)),
         Cmd::NextHistory => rustyline::Cmd::NextHistory,
+        Cmd::Newline => rustyline::Cmd::Newline,
         Cmd::Noop => rustyline::Cmd::Noop,
         Cmd::Overwrite(c) => rustyline::Cmd::Overwrite(c),
+        #[cfg(windows)]
+        Cmd::PasteFromClipboard => rustyline::Cmd::PasteFromClipboard,
         Cmd::PreviousHistory => rustyline::Cmd::PreviousHistory,
         Cmd::QuotedInsert => rustyline::Cmd::QuotedInsert,
         Cmd::Replace {
@@ -169,14 +153,28 @@ fn convert_cmd(cmd: Cmd) -> rustyline::Cmd {
 }
 
 fn convert_keybinding(keybinding: Keybinding) -> (rustyline::KeyEvent, rustyline::Cmd) {
+    let rusty_modifiers = match keybinding.modifiers {
+        Some(mods) => match mods {
+            NuModifiers::CTRL => Some(Modifiers::CTRL),
+            NuModifiers::ALT => Some(Modifiers::ALT),
+            NuModifiers::SHIFT => Some(Modifiers::SHIFT),
+            NuModifiers::NONE => Some(Modifiers::NONE),
+            NuModifiers::CTRL_SHIFT => Some(Modifiers::CTRL_SHIFT),
+            NuModifiers::ALT_SHIFT => Some(Modifiers::ALT_SHIFT),
+            NuModifiers::CTRL_ALT => Some(Modifiers::CTRL_ALT),
+            NuModifiers::CTRL_ALT_SHIFT => Some(Modifiers::CTRL_ALT_SHIFT),
+            // _ => None,
+        },
+        None => None,
+    };
     (
-        convert_keyevent(keybinding.key),
+        convert_keyevent(keybinding.key, rusty_modifiers),
         convert_cmd(keybinding.binding),
     )
 }
 
 #[derive(Serialize, Deserialize, Debug, Clone)]
-pub enum KeyEvent {
+pub enum KeyCode {
     /// Unsupported escape sequence (on unix platform)
     UnknownEscSeq,
     /// ⌫ or `KeyEvent::Ctrl('H')`
@@ -189,16 +187,6 @@ pub enum KeyEvent {
     BracketedPasteEnd,
     /// Single char
     Char(char),
-    /// Ctrl-↓
-    ControlDown,
-    /// Ctrl-←
-    ControlLeft,
-    /// Ctrl-→
-    ControlRight,
-    /// Ctrl-↑
-    ControlUp,
-    /// Ctrl-char
-    Ctrl(char),
     /// ⌦
     Delete,
     /// ↓ arrow key
@@ -217,9 +205,7 @@ pub enum KeyEvent {
     Insert,
     /// ← arrow key
     Left,
-    /// Escape-char or Alt-char
+    // /// `KeyEvent::Char('\0')`
-    Meta(char),
-    /// `KeyEvent::Char('\0')`
     Null,
     /// ⇟
     PageDown,
@@ -227,14 +213,6 @@ pub enum KeyEvent {
     PageUp,
     /// → arrow key
     Right,
-    /// Shift-↓
-    ShiftDown,
-    /// Shift-←
-    ShiftLeft,
-    /// Shift-→
-    ShiftRight,
-    /// Shift-↑
-    ShiftUp,
     /// ⇥ or `KeyEvent::Ctrl('I')`
     Tab,
     /// ↑ arrow key
@@ -259,6 +237,8 @@ pub enum Cmd {
     CompleteBackward,
     /// complete-hint
     CompleteHint,
+    /// Dedent current line
+    Dedent(Movement),
     /// downcase-word
     DowncaseWord,
     /// vi-eof-maybe
@@ -271,6 +251,8 @@ pub enum Cmd {
     HistorySearchBackward,
     /// history-search-forward
     HistorySearchForward,
+    /// Indent current line
+    Indent(Movement),
     /// Insert text
     Insert { repeat: RepeatCount, string: String },
     /// Interrupt signal (Ctrl-C)
@@ -283,12 +265,17 @@ pub enum Cmd {
     /// forward-char, forward-word, vi-char-search, vi-end-word, vi-next-word,
     /// vi-prev-word
     Move(Movement),
+    /// Inserts a newline
+    Newline,
     /// next-history
     NextHistory,
     /// No action
     Noop,
     /// vi-replace
     Overwrite(char),
+    /// Paste from the clipboard
+    #[cfg(windows)]
+    PasteFromClipboard,
     /// previous-history
     PreviousHistory,
     /// quoted-insert
@@ -422,12 +409,36 @@ pub enum CharSearch {
     BackwardAfter(char),
 }
 
+/// The set of modifier keys that were triggered along with a key press.
+#[derive(Serialize, Deserialize)]
+#[allow(non_camel_case_types)]
+#[allow(clippy::clippy::upper_case_acronyms)]
+pub enum NuModifiers {
+    /// Control modifier
+    CTRL = 8,
+    /// Escape or Alt modifier
+    ALT = 4,
+    /// Shift modifier
+    SHIFT = 2,
+    /// No modifier
+    NONE = 0,
+    /// Ctrl + Shift
+    CTRL_SHIFT = 10,
+    /// Alt + Shift
+    ALT_SHIFT = 6,
+    /// Ctrl + Alt
+    CTRL_ALT = 12,
+    /// Ctrl + Alt + Shift
+    CTRL_ALT_SHIFT = 14,
+}
+
 /// The number of times one command should be repeated.
 pub type RepeatCount = usize;
 
-#[derive(Serialize, Deserialize, Debug, Clone)]
+#[derive(Serialize, Deserialize)]
 pub struct Keybinding {
-    key: KeyEvent,
+    key: KeyCode,
+    modifiers: Option<NuModifiers>,
     binding: Cmd,
 }
 
@@ -442,7 +453,7 @@ pub(crate) fn load_keybindings(
     // Silently fail if there is no file there
     if let Ok(contents) = contents {
         let keybindings: Keybindings = serde_yaml::from_str(&contents)?;
-
+        // eprint!("{}{}{}", keybindings.key, keybindings.mo);
         for keybinding in keybindings.into_iter() {
             let (k, b) = convert_keybinding(keybinding);
 

crates/nu-cli/src/line_editor.rs

@@ -8,7 +8,7 @@ use crate::prelude::*;
 use nu_engine::script::LineResult;
 
 #[cfg(feature = "rustyline-support")]
-use crate::keybinding::{convert_keyevent, KeyEvent};
+use crate::keybinding::{convert_keyevent, KeyCode};
 
 #[cfg(feature = "rustyline-support")]
 use crate::shell::Helper;
@@ -19,7 +19,8 @@ use rustyline::{
     config::Configurer,
     config::{ColorMode, CompletionType, Config},
     error::ReadlineError,
-    At, Cmd, Editor, Movement, Word,
+    line_buffer::LineBuffer,
+    At, Cmd, ConditionalEventHandler, Editor, EventHandler, Modifiers, Movement, Word,
 };
 
 #[cfg(feature = "rustyline-support")]
@@ -36,6 +37,34 @@ pub fn convert_rustyline_result_to_string(input: Result<String, ReadlineError>)
     }
 }
 
+#[derive(Clone)]
+#[cfg(feature = "rustyline-support")]
+struct PartialCompleteHintHandler;
+
+#[cfg(feature = "rustyline-support")]
+impl ConditionalEventHandler for PartialCompleteHintHandler {
+    fn handle(
+        &self,
+        _evt: &rustyline::Event,
+        _n: rustyline::RepeatCount,
+        _positive: bool,
+        ctx: &rustyline::EventContext,
+    ) -> Option<Cmd> {
+        Some(match ctx.hint_text() {
+            Some(hint_text) if ctx.pos() == ctx.line().len() => {
+                let mut line_buffer = LineBuffer::with_capacity(hint_text.len());
+                line_buffer.update(hint_text, 0);
+                line_buffer.move_to_next_word(At::AfterEnd, Word::Vi, 1);
+
+                let text = hint_text[0..line_buffer.pos()].to_string();
+
+                Cmd::Insert(1, text)
+            }
+            _ => Cmd::Move(Movement::ForwardWord(1, At::AfterEnd, Word::Vi)),
+        })
+    }
+}
+
 #[cfg(feature = "rustyline-support")]
 pub fn default_rustyline_editor_configuration() -> Editor<Helper> {
     #[cfg(windows)]
@@ -50,18 +79,20 @@ pub fn default_rustyline_editor_configuration() -> Editor<Helper> {
     let mut rl: Editor<_> = Editor::with_config(config);
 
     // add key bindings to move over a whole word with Ctrl+ArrowLeft and Ctrl+ArrowRight
+    //M modifier, E KeyEvent, K KeyCode
     rl.bind_sequence(
-        convert_keyevent(KeyEvent::ControlLeft),
+        convert_keyevent(KeyCode::Left, Some(Modifiers::CTRL)),
         Cmd::Move(Movement::BackwardWord(1, Word::Vi)),
     );
+
     rl.bind_sequence(
-        convert_keyevent(KeyEvent::ControlRight),
+        convert_keyevent(KeyCode::Right, Some(Modifiers::CTRL)),
-        Cmd::Move(Movement::ForwardWord(1, At::AfterEnd, Word::Vi)),
+        EventHandler::Conditional(Box::new(PartialCompleteHintHandler)),
     );
 
     // workaround for multiline-paste hang in rustyline (see https://github.com/kkawakam/rustyline/issues/202)
     rl.bind_sequence(
-        convert_keyevent(KeyEvent::BracketedPasteStart),
+        convert_keyevent(KeyCode::BracketedPasteStart, None),
         rustyline::Cmd::Noop,
     );
     // Let's set the defaults up front and then override them later if the user indicates

crates/nu-cli/src/shell/completer.rs

@@ -44,6 +44,10 @@ impl NuCompleter {
         let matcher = matcher.as_str();
         let matcher: &dyn Matcher = match matcher {
             "case-insensitive" => &matchers::case_insensitive::Matcher,
+            "case-sensitive" => &matchers::case_sensitive::Matcher,
+            #[cfg(target_os = "windows")]
+            _ => &matchers::case_insensitive::Matcher,
+            #[cfg(not(target_os = "windows"))]
             _ => &matchers::case_sensitive::Matcher,
         };
 
@@ -134,7 +138,7 @@ fn requote(orig_value: String) -> String {
     let mut quotes = vec!['"', '\'', '`'];
     let mut should_quote = false;
     for c in value.chars() {
-        if c.is_whitespace() {
+        if c.is_whitespace() || c == '#' {
             should_quote = true;
         } else if let Some(index) = quotes.iter().position(|q| *q == c) {
             should_quote = true;
@@ -145,7 +149,7 @@ fn requote(orig_value: String) -> String {
     if should_quote {
         if quotes.is_empty() {
             // TODO we don't really have an escape character, so there isn't a great option right
-            //      now. One possibility is `{{$(char backtick)}}`
+            //      now. One possibility is `{{(char backtick)}}`
             value.to_string()
         } else {
             let quote = quotes[0];

crates/nu-cli/src/shell/helper.rs

@@ -150,7 +150,7 @@ impl rustyline::Helper for Helper {}
 #[cfg(test)]
 mod tests {
     use super::*;
-    use nu_engine::basic_evaluation_context;
+    use nu_engine::EvaluationContext;
     use rustyline::completion::Completer;
     use rustyline::line_buffer::LineBuffer;
 
@@ -164,7 +164,7 @@ mod tests {
         buffer.insert_str(0, text);
         buffer.set_pos(text.len() - 1);
 
-        let helper = Helper::new(basic_evaluation_context().unwrap(), None);
+        let helper = Helper::new(EvaluationContext::basic(), None);
 
         helper.update(&mut buffer, "cd ".len(), &replacement);
 
@@ -184,7 +184,7 @@ mod tests {
         buffer.insert_str(0, text);
         buffer.set_pos(text.len() - 30);
 
-        let helper = Helper::new(basic_evaluation_context().unwrap(), None);
+        let helper = Helper::new(EvaluationContext::basic(), None);
 
         helper.update(&mut buffer, "cd ".len(), &replacement);
 

crates/nu-cli/src/types/deduction.rs

@@ -81,29 +81,29 @@ lazy_static! {
     static ref MULT_DIV_LOOKUP_TABLE: HashMap<(Operator, BinarySide, SyntaxShape), Vec<SyntaxShape>> = {
         vec![
             ((Operator::Divide, BinarySide::Left, SyntaxShape::Number),       // expr => possible var shapes
-             vec![SyntaxShape::Unit, SyntaxShape::Number, SyntaxShape::Int]), //$var / number => Unit, Int, Number
+             vec![SyntaxShape::Filesize, SyntaxShape::Duration, SyntaxShape::Number, SyntaxShape::Int]), //$var / number => Unit, Int, Number
             ((Operator::Divide, BinarySide::Left, SyntaxShape::Int),
-             vec![SyntaxShape::Unit, SyntaxShape::Number, SyntaxShape::Int]), //$var / int => Unit, Int, Number
+             vec![SyntaxShape::Filesize, SyntaxShape::Duration, SyntaxShape::Number, SyntaxShape::Int]), //$var / int => Unit, Int, Number
-            ((Operator::Divide, BinarySide::Left, SyntaxShape::Unit),
+            ((Operator::Divide, BinarySide::Left, SyntaxShape::Filesize),
-             vec![SyntaxShape::Unit]), //$var / unit => Unit
+             vec![SyntaxShape::Filesize, SyntaxShape::Duration, SyntaxShape::Filesize]), //$var / unit => Unit
             ((Operator::Divide, BinarySide::Right, SyntaxShape::Number),
              vec![SyntaxShape::Number, SyntaxShape::Int]), //number / $var => Int, Number
             ((Operator::Divide, BinarySide::Right, SyntaxShape::Int),
              vec![SyntaxShape::Number, SyntaxShape::Int]), //int / $var => Int, Number
-            ((Operator::Divide, BinarySide::Right, SyntaxShape::Unit),
+            ((Operator::Divide, BinarySide::Right, SyntaxShape::Filesize),
-             vec![SyntaxShape::Unit, SyntaxShape::Number, SyntaxShape::Int]), //unit / $var => unit, int, number
+             vec![SyntaxShape::Filesize, SyntaxShape::Number, SyntaxShape::Int]), //unit / $var => unit, int, number
 
             ((Operator::Multiply, BinarySide::Left, SyntaxShape::Number),
-             vec![SyntaxShape::Unit, SyntaxShape::Number, SyntaxShape::Int]), //$var * number => Unit, Int, Number
+             vec![SyntaxShape::Filesize, SyntaxShape::Number, SyntaxShape::Int]), //$var * number => Unit, Int, Number
             ((Operator::Multiply, BinarySide::Left, SyntaxShape::Int),
-             vec![SyntaxShape::Unit, SyntaxShape::Number, SyntaxShape::Int]), //$var * int => Unit, Int, Number
+             vec![SyntaxShape::Filesize, SyntaxShape::Number, SyntaxShape::Int]), //$var * int => Unit, Int, Number
-            ((Operator::Multiply, BinarySide::Left, SyntaxShape::Unit),
+            ((Operator::Multiply, BinarySide::Left, SyntaxShape::Filesize),
              vec![SyntaxShape::Int, SyntaxShape::Number]), //$var * unit => int, number //TODO this changes as soon as more complex units arrive
             ((Operator::Multiply, BinarySide::Right, SyntaxShape::Number),
-             vec![SyntaxShape::Unit, SyntaxShape::Number, SyntaxShape::Int]), //number * $var => Unit, Int, Number
+             vec![SyntaxShape::Filesize, SyntaxShape::Number, SyntaxShape::Int]), //number * $var => Unit, Int, Number
             ((Operator::Multiply, BinarySide::Right, SyntaxShape::Int),
-             vec![SyntaxShape::Unit, SyntaxShape::Number, SyntaxShape::Int]), //int * $var => Unit, Int, Number
+             vec![SyntaxShape::Filesize, SyntaxShape::Number, SyntaxShape::Int]), //int * $var => Unit, Int, Number
-            ((Operator::Multiply, BinarySide::Right, SyntaxShape::Unit),
+            ((Operator::Multiply, BinarySide::Right, SyntaxShape::Filesize),
              vec![SyntaxShape::Int, SyntaxShape::Number]), //unit * $var => int, number //TODO this changes as soon as more complex units arrive
             ].into_iter().collect()
     };
@@ -241,8 +241,8 @@ fn get_result_shape_of(
             l_shape
         }
         Operator::Multiply => {
-            if l_shape == SyntaxShape::Unit || r_shape == SyntaxShape::Unit {
+            if l_shape == SyntaxShape::Duration || r_shape == SyntaxShape::Duration {
-                SyntaxShape::Unit
+                SyntaxShape::Duration
             } else {
                 SyntaxShape::Number
             }
@@ -250,7 +250,7 @@ fn get_result_shape_of(
         Operator::Divide => {
             if l_shape == r_shape {
                 SyntaxShape::Number
-            } else if l_shape == SyntaxShape::Unit {
+            } else if l_shape == SyntaxShape::Duration {
                 l_shape
             } else {
                 SyntaxShape::Number
@@ -273,10 +273,11 @@ fn get_shape_of_expr(expr: &SpannedExpression) -> Option<SyntaxShape> {
         Expression::Literal(literal) => {
             match literal {
                 nu_protocol::hir::Literal::Number(number) => match number {
+                    nu_protocol::hir::Number::BigInt(_) => Some(SyntaxShape::Int),
                     nu_protocol::hir::Number::Int(_) => Some(SyntaxShape::Int),
                     nu_protocol::hir::Number::Decimal(_) => Some(SyntaxShape::Number),
                 },
-                nu_protocol::hir::Literal::Size(_, _) => Some(SyntaxShape::Unit),
+                nu_protocol::hir::Literal::Size(_, _) => Some(SyntaxShape::Duration),
                 nu_protocol::hir::Literal::String(_) => Some(SyntaxShape::String),
                 //Rest should have failed at parsing stage?
                 nu_protocol::hir::Literal::GlobPattern(_) => Some(SyntaxShape::String),
@@ -295,7 +296,7 @@ fn get_shape_of_expr(expr: &SpannedExpression) -> Option<SyntaxShape> {
         Expression::List(_) => Some(SyntaxShape::Table),
         Expression::Boolean(_) => Some(SyntaxShape::String),
 
-        Expression::Path(_) => Some(SyntaxShape::ColumnPath),
+        Expression::FullColumnPath(_) => Some(SyntaxShape::ColumnPath),
         Expression::FilePath(_) => Some(SyntaxShape::FilePath),
         Expression::Block(_) => Some(SyntaxShape::Block),
         Expression::ExternalCommand(_) => Some(SyntaxShape::String),
@@ -377,10 +378,7 @@ impl VarSyntaxShapeDeductor {
             .iter()
             .map(|decl| {
                 let usage: VarUsage = decl.into();
-                let deduction = match deducer.inferences.get(&usage) {
+                let deduction = deducer.inferences.get(&usage).cloned();
-                    Some(vec) => Some(vec.clone()),
-                    None => None,
-                };
                 (decl.clone(), deduction)
             })
             .collect())
@@ -541,7 +539,7 @@ impl VarSyntaxShapeDeductor {
                 trace!("Inferring vars in block");
                 self.infer_shape(&b, scope)?;
             }
-            Expression::Path(path) => {
+            Expression::FullColumnPath(path) => {
                 trace!("Inferring vars in path");
                 match &path.head.expr {
                     //PathMember can't be var yet (?)
@@ -792,7 +790,7 @@ impl VarSyntaxShapeDeductor {
                         | Expression::Binary(_)
                         | Expression::Range(_)
                         | Expression::Block(_)
-                        | Expression::Path(_)
+                        | Expression::FullColumnPath(_)
                         | Expression::FilePath(_)
                         | Expression::ExternalCommand(_)
                         | Expression::Command
@@ -845,12 +843,21 @@ impl VarSyntaxShapeDeductor {
                                     ),
                                 )?;
                             }
-                            SyntaxShape::Unit => {
+                            SyntaxShape::Duration => {
                                 self.checked_insert(
                                     var,
                                     VarShapeDeduction::from_usage_with_alternatives(
                                         &var.span,
-                                        &[SyntaxShape::Unit],
+                                        &[SyntaxShape::Duration],
+                                    ),
+                                )?;
+                            }
+                            SyntaxShape::Filesize => {
+                                self.checked_insert(
+                                    var,
+                                    VarShapeDeduction::from_usage_with_alternatives(
+                                        &var.span,
+                                        &[SyntaxShape::Filesize],
                                     ),
                                 )?;
                             }
@@ -1023,7 +1030,7 @@ impl VarSyntaxShapeDeductor {
                                     Some(combination)
                                 }
                             })
-                            .filter_map(|elem| elem)
+                            .flatten()
                             .collect()
                         }
                         //No any's intersection of both is result
@@ -1044,7 +1051,7 @@ impl VarSyntaxShapeDeductor {
                                         Some(combination)
                                     }
                                 })
-                                .filter_map(|elem| elem)
+                                .flatten()
                                 .collect();
                             if intersection.is_empty() {
                                 //TODO pass all labels somehow

crates/nu-command/Cargo.toml

@@ -5,25 +5,26 @@ description = "CLI for nushell"
 edition = "2018"
 license = "MIT"
 name = "nu-command"
-version = "0.30.0"
+version = "0.32.0"
 
 [lib]
 doctest = false
 
 [dependencies]
-nu-data = { version = "0.30.0", path = "../nu-data" }
+nu-data = { version = "0.32.0", path = "../nu-data" }
-nu-engine = { version = "0.30.0", path = "../nu-engine" }
+nu-engine = { version = "0.32.0", path = "../nu-engine" }
-nu-errors = { version = "0.30.0", path = "../nu-errors" }
+nu-errors = { version = "0.32.0", path = "../nu-errors" }
-nu-json = { version = "0.30.0", path = "../nu-json" }
+nu-json = { version = "0.32.0", path = "../nu-json" }
-nu-parser = { version = "0.30.0", path = "../nu-parser" }
+nu-parser = { version = "0.32.0", path = "../nu-parser" }
-nu-plugin = { version = "0.30.0", path = "../nu-plugin" }
+nu-plugin = { version = "0.32.0", path = "../nu-plugin" }
-nu-protocol = { version = "0.30.0", path = "../nu-protocol" }
+nu-protocol = { version = "0.32.0", path = "../nu-protocol" }
-nu-source = { version = "0.30.0", path = "../nu-source" }
+nu-source = { version = "0.32.0", path = "../nu-source" }
-nu-stream = { version = "0.30.0", path = "../nu-stream" }
+nu-stream = { version = "0.32.0", path = "../nu-stream" }
-nu-table = { version = "0.30.0", path = "../nu-table" }
+nu-table = { version = "0.32.0", path = "../nu-table" }
-nu-test-support = { version = "0.30.0", path = "../nu-test-support" }
+nu-test-support = { version = "0.32.0", path = "../nu-test-support" }
-nu-value-ext = { version = "0.30.0", path = "../nu-value-ext" }
+nu-value-ext = { version = "0.32.0", path = "../nu-value-ext" }
-nu-ansi-term = { version = "0.30.0", path = "../nu-ansi-term" }
+nu-ansi-term = { version = "0.32.0", path = "../nu-ansi-term" }
+nu-pretty-hex = { version = "0.32.0", path = "../nu-pretty-hex" }
 
 Inflector = "0.11"
 arboard = { version = "1.1.0", optional = true }
@@ -53,7 +54,6 @@ getset = "0.1.1"
 glob = "0.3.0"
 htmlescape = "0.3.1"
 ical = "0.7.0"
-ichwh = { version = "0.3.4", optional = true }
 indexmap = { version = "1.6.1", features = ["serde-1"] }
 itertools = "0.10.0"
 lazy_static = "1.*"
@@ -66,7 +66,6 @@ num-format = { version = "0.4.0", features = ["with-num-bigint"] }
 num-traits = "0.2.14"
 parking_lot = "0.11.1"
 pin-utils = "0.1.0"
-pretty-hex = "0.2.1"
 ptree = { version = "0.3.1", optional = true }
 query_interface = "0.3.5"
 quick-xml = "0.21.0"
@@ -75,7 +74,7 @@ rayon = "1.5.0"
 regex = "1.4.3"
 roxmltree = "0.14.0"
 rust-embed = "5.9.0"
-rustyline = { version = "8.0.0", optional = true }
+rustyline = { version = "8.1.0", optional = true }
 serde = { version = "1.0.123", features = ["derive"] }
 serde_bytes = "0.11.5"
 serde_ini = "0.2.0"
@@ -97,9 +96,14 @@ trash = { version = "1.3.0", optional = true }
 unicode-segmentation = "1.7.1"
 url = "2.2.0"
 uuid_crate = { package = "uuid", version = "0.8.2", features = ["v4"], optional = true }
-which = { version = "4.0.2", optional = true }
+which = { version = "4.1.0", optional = true }
 zip = { version = "0.5.9", optional = true }
 
+[dependencies.polars]
+version = "0.13.4"
+optional = true
+features = ["parquet", "json", "random"]
+
 [target.'cfg(unix)'.dependencies]
 umask = "1.0.0"
 users = "0.11.0"
@@ -113,7 +117,7 @@ users = "0.11.0"
 [dependencies.rusqlite]
 features = ["bundled", "blob"]
 optional = true
-version = "0.24.2"
+version = "0.25.3"
 
 [build-dependencies]
 shadow-rs = "0.5"
@@ -131,3 +135,4 @@ trash-support = ["trash"]
 directories = ["directories-next"]
 dirs = ["dirs-next"]
 table-pager = ["minus", "crossterm"]
+dataframe = ["nu-protocol/dataframe", "polars"]

crates/nu-command/src/commands.rs

@@ -26,6 +26,8 @@ pub(crate) mod compact;
 pub(crate) mod config;
 pub(crate) mod constants;
 pub(crate) mod cp;
+#[cfg(feature = "dataframe")]
+pub(crate) mod dataframe;
 pub(crate) mod date;
 pub(crate) mod debug;
 pub(crate) mod def;
@@ -44,6 +46,7 @@ pub(crate) mod exec;
 pub(crate) mod exit;
 pub(crate) mod first;
 pub(crate) mod flatten;
+pub(crate) mod for_in;
 pub(crate) mod format;
 pub(crate) mod from;
 pub(crate) mod from_csv;
@@ -77,6 +80,7 @@ pub(crate) mod length;
 pub(crate) mod let_;
 pub(crate) mod let_env;
 pub(crate) mod lines;
+pub(crate) mod load_env;
 pub(crate) mod ls;
 pub(crate) mod math;
 pub(crate) mod merge;
@@ -170,9 +174,12 @@ pub(crate) use each::EachGroup;
 pub(crate) use each::EachWindow;
 pub(crate) use echo::Echo;
 pub(crate) use empty::Command as Empty;
+pub(crate) use for_in::ForIn;
 pub(crate) use if_::If;
 pub(crate) use into::Into;
+pub(crate) use into::IntoBinary;
 pub(crate) use into::IntoInt;
+pub(crate) use into::IntoString;
 pub(crate) use nu::NuPlugin;
 pub(crate) use update::Command as Update;
 pub(crate) mod kill;
@@ -182,6 +189,12 @@ pub(crate) use clear::Clear;
 pub(crate) mod touch;
 pub(crate) use all::Command as All;
 pub(crate) use any::Command as Any;
+#[cfg(feature = "dataframe")]
+pub(crate) use dataframe::{
+    DataFrame, DataFrameAggregate, DataFrameConvert, DataFrameDTypes, DataFrameDrop,
+    DataFrameGroupBy, DataFrameJoin, DataFrameList, DataFrameLoad, DataFrameSample,
+    DataFrameSelect, DataFrameShow,
+};
 pub(crate) use enter::Enter;
 pub(crate) use every::Every;
 pub(crate) use exec::Exec;
@@ -220,6 +233,7 @@ pub(crate) use length::Length;
 pub(crate) use let_::Let;
 pub(crate) use let_env::LetEnv;
 pub(crate) use lines::Lines;
+pub(crate) use load_env::LoadEnv;
 pub(crate) use ls::Ls;
 pub(crate) use math::{
     Math, MathAbs, MathAverage, MathCeil, MathEval, MathFloor, MathMaximum, MathMedian,
@@ -234,8 +248,8 @@ pub(crate) use nth::Nth;
 pub(crate) use open::Open;
 pub(crate) use parse::Parse;
 pub(crate) use path::{
-    PathBasename, PathCommand, PathDirname, PathExists, PathExpand, PathJoin, PathParse, PathSplit,
+    PathBasename, PathCommand, PathDirname, PathExists, PathExpand, PathJoin, PathParse,
-    PathType,
+    PathRelativeTo, PathSplit, PathType,
 };
 pub(crate) use pivot::Pivot;
 pub(crate) use prepend::Prepend;
@@ -270,7 +284,7 @@ pub(crate) use split::{Split, SplitChars, SplitColumn, SplitRow};
 pub(crate) use split_by::SplitBy;
 pub(crate) use str_::{
     Str, StrCamelCase, StrCapitalize, StrCollect, StrContains, StrDowncase, StrEndsWith,
-    StrFindReplace, StrFrom, StrIndexOf, StrKebabCase, StrLPad, StrLength, StrPascalCase, StrRPad,
+    StrFindReplace, StrIndexOf, StrKebabCase, StrLPad, StrLength, StrPascalCase, StrRPad,
     StrReverse, StrScreamingSnakeCase, StrSnakeCase, StrStartsWith, StrSubstring, StrToDatetime,
     StrToDecimal, StrToInteger, StrTrim, StrTrimLeft, StrTrimRight, StrUpcase,
 };
@@ -321,7 +335,6 @@ mod tests {
             whole_stream_command(StrUpcase),
             whole_stream_command(StrCapitalize),
             whole_stream_command(StrFindReplace),
-            whole_stream_command(StrFrom),
             whole_stream_command(StrSubstring),
             whole_stream_command(StrToDatetime),
             whole_stream_command(StrContains),
@@ -354,6 +367,7 @@ mod tests {
     #[test]
     fn examples_work_as_expected() -> Result<(), ShellError> {
         for cmd in only_examples() {
+            println!("cmd: {}", cmd.name());
             test_examples(cmd)?;
         }
 

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

@@ -44,7 +44,7 @@ impl WholeStreamCommand for Command {
             },
             Example {
                 description: "Check that all values are even",
-                example: "echo [2 4 6 8] | all? $(= $it mod 2) == 0",
+                example: "echo [2 4 6 8] | all? ($it mod 2) == 0",
                 result: Some(vec![Value::from(true)]),
             },
         ]
@@ -83,13 +83,13 @@ fn all(args: CommandArgs) -> Result<OutputStream, ShellError> {
         }
     };
 
-    let scope = args.scope.clone();
+    let scope = args.scope();
 
     let init = Ok(InputStream::one(
         UntaggedValue::boolean(true).into_value(&tag),
     ));
 
-    // Variables in nu are immutable. Having the same variable accross invocations
+    // Variables in nu are immutable. Having the same variable across invocations
     // of evaluate_baseline_expr does not mutate the variables and those each
     // invocations are independent of each other!
     scope.enter_scope();

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

@@ -2,7 +2,7 @@ use crate::prelude::*;
 use nu_ansi_term::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_protocol::{Signature, SyntaxShape, UntaggedValue, Value};
 use nu_source::Tagged;
 
 pub struct Command;
@@ -69,7 +69,7 @@ following values:
     https://en.wikipedia.org/wiki/ANSI_escape_code
 
 OSC: '\x1b]' is not required for --osc parameter
-Example: echo [$(ansi -o '0') 'some title' $(char bel)] | str collect
+Example: echo [(ansi -o '0') 'some title' (char bel)] | str collect
 Format: #
     0 Set window title and icon name
     1 Set icon name
@@ -96,7 +96,7 @@ Format: #
             Example {
                 description:
                     "Use ansi to color text (rb = red bold, gb = green bold, pb = purple bold)",
-                example: r#"echo [$(ansi rb) Hello " " $(ansi gb) Nu " " $(ansi pb) World] | str collect"#,
+                example: r#"echo [(ansi rb) Hello " " (ansi gb) Nu " " (ansi pb) World] | str collect"#,
                 result: Some(vec![Value::from(
                     "\u{1b}[1;31mHello \u{1b}[1;32mNu \u{1b}[1;35mWorld",
                 )]),
@@ -104,7 +104,7 @@ Format: #
             Example {
                 description:
                     "Use ansi to color text (rb = red bold, gb = green bold, pb = purple bold)",
-                example: r#"echo [$(ansi -e '3;93;41m') Hello $(ansi reset) " " $(ansi gb) Nu " " $(ansi pb) World] | str collect"#,
+                example: r#"echo [(ansi -e '3;93;41m') Hello (ansi reset) " " (ansi gb) Nu " " (ansi pb) World] | str collect"#,
                 result: Some(vec![Value::from(
                     "\u{1b}[3;93;41mHello\u{1b}[0m \u{1b}[1;32mNu \u{1b}[1;35mWorld",
                 )]),
@@ -112,7 +112,7 @@ Format: #
         ]
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         let args = args.evaluate_once()?;
 
         let code: Option<Tagged<String>> = args.opt(0)?;
@@ -129,9 +129,9 @@ Format: #
                 ));
             }
             let output = format!("\x1b[{}", e.item);
-            return Ok(ActionStream::one(ReturnSuccess::value(
+            return Ok(OutputStream::one(
                 UntaggedValue::string(output).into_value(e.tag()),
-            )));
+            ));
         }
 
         if let Some(o) = osc {
@@ -147,18 +147,18 @@ Format: #
             //Operating system command aka osc  ESC ] <- note the right brace, not left brace for osc
             // OCS's need to end with a bell '\x07' char
             let output = format!("\x1b]{};", o.item);
-            return Ok(ActionStream::one(ReturnSuccess::value(
+            return Ok(OutputStream::one(
                 UntaggedValue::string(output).into_value(o.tag()),
-            )));
+            ));
         }
 
         if let Some(code) = code {
             let ansi_code = str_to_ansi(&code.item);
 
             if let Some(output) = ansi_code {
-                Ok(ActionStream::one(ReturnSuccess::value(
+                Ok(OutputStream::one(
                     UntaggedValue::string(output).into_value(code.tag()),
-                )))
+                ))
             } else {
                 Err(ShellError::labeled_error(
                     "Unknown ansi code",
@@ -299,7 +299,7 @@ pub fn str_to_ansi(s: &str) -> Option<String> {
         // Reference for ansi codes https://gist.github.com/fnky/458719343aabd01cfb17a3a4f7296797
         // Another good reference http://ascii-table.com/ansi-escape-sequences.php
 
-        // For setting title like `echo [$(char title) $(pwd) $(char bel)] | str collect`
+        // For setting title like `echo [(char title) (pwd) (char bel)] | str collect`
         "title" => Some("\x1b]2;".to_string()), // ESC]2; xterm sets window title using OSC syntax escapes
 
         // Ansi Erase Sequences

crates/nu-command/src/commands/ansi/strip.rs

@@ -2,19 +2,12 @@ use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
 use nu_protocol::ShellTypeName;
-use nu_protocol::{
+use nu_protocol::{Primitive, Signature, SyntaxShape, UntaggedValue, Value};
-    ColumnPath, Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
-};
 use nu_source::Tag;
 use strip_ansi_escapes::strip;
 
 pub struct SubCommand;
 
-#[derive(Deserialize)]
-struct Arguments {
-    rest: Vec<ColumnPath>,
-}
-
 impl WholeStreamCommand for SubCommand {
     fn name(&self) -> &str {
         "ansi strip"
@@ -31,27 +24,29 @@ impl WholeStreamCommand for SubCommand {
         "strip ansi escape sequences from string"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         operate(args)
     }
 
     fn examples(&self) -> Vec<Example> {
         vec![Example {
             description: "strip ansi escape sequences from string",
-            example: "echo [$(ansi gb) 'hello' $(ansi reset)] | str collect | ansi strip",
+            example: "echo [(ansi gb) 'hello' (ansi reset)] | str collect | ansi strip",
             result: None,
         }]
     }
 }
 
-fn operate(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn operate(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let (Arguments { rest }, input) = args.process()?;
+    let args = args.evaluate_once()?;
-    let column_paths: Vec<_> = rest;
 
-    Ok(input
+    let column_paths: Vec<_> = args.rest(0)?;
+
+    let result: Vec<Value> = args
+        .input
         .map(move |v| {
             if column_paths.is_empty() {
-                ReturnSuccess::value(action(&v, v.tag())?)
+                action(&v, v.tag())
             } else {
                 let mut ret = v;
 
@@ -62,10 +57,12 @@ fn operate(args: CommandArgs) -> Result<ActionStream, ShellError> {
                     )?;
                 }
 
-                ReturnSuccess::value(ret)
+                Ok(ret)
             }
         })
-        .to_action_stream())
+        .collect::<Result<Vec<Value>, _>>()?;
+
+    Ok(OutputStream::from_stream(result.into_iter()))
 }
 
 fn action(input: &Value, tag: impl Into<Tag>) -> Result<Value, ShellError> {

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

@@ -8,9 +8,8 @@ use nu_protocol::{
 
 pub struct Command;
 
-#[derive(Deserialize)]
+struct AnyArgs {
-pub struct Arguments {
+    predicate: CapturedBlock,
-    block: CapturedBlock,
 }
 
 impl WholeStreamCommand for Command {
@@ -30,7 +29,7 @@ impl WholeStreamCommand for Command {
         "Find if the table rows matches the condition."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         any(args)
     }
 
@@ -45,79 +44,85 @@ impl WholeStreamCommand for Command {
             },
             Example {
                 description: "Check if any of the values is odd",
-                example: "echo [2 4 1 6 8] | any? $(= $it mod 2) == 1",
+                example: "echo [2 4 1 6 8] | any? ($it mod 2) == 1",
                 result: Some(vec![Value::from(true)]),
             },
         ]
     }
 }
 
-fn any(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn any(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let ctx = Arc::new(EvaluationContext::from_args(&args));
+    let ctx = EvaluationContext::from_args(&args);
     let tag = args.call_info.name_tag.clone();
-    let (Arguments { block }, input) = args.process()?;
+    let args = args.evaluate_once()?;
+    let any_args = AnyArgs {
+        predicate: args.req(0)?,
+    };
 
+    let err = Err(ShellError::labeled_error(
+        "Expected a condition",
+        "expected a condition",
+        args.call_info.name_tag.clone(),
+    ));
+
+    //This seems a little odd. Can't we have predicates with pipelines/multiple statements?
     let condition = {
-        if block.block.block.len() != 1 {
+        if any_args.predicate.block.block.len() != 1 {
-            return Err(ShellError::labeled_error(
+            return err;
-                "Expected a condition",
-                "expected a condition",
-                tag,
-            ));
         }
-        match block.block.block[0].pipelines.get(0) {
+        match any_args.predicate.block.block[0].pipelines.get(0) {
             Some(item) => match item.list.get(0) {
                 Some(ClassifiedCommand::Expr(expr)) => expr.clone(),
                 _ => {
-                    return Err(ShellError::labeled_error(
+                    return err;
-                        "Expected a condition",
-                        "expected a condition",
-                        tag,
-                    ));
                 }
             },
             None => {
-                return Err(ShellError::labeled_error(
+                return err;
-                    "Expected a condition",
-                    "expected a condition",
-                    tag,
-                ));
             }
         }
     };
 
-    let cond = Ok(InputStream::one(
+    let scope = args.scope();
+
+    let init = Ok(InputStream::one(
         UntaggedValue::boolean(false).into_value(&tag),
     ));
 
-    Ok(input
+    // Variables in nu are immutable. Having the same variable accross invocations
-        .fold(cond, move |cond, row| {
+    // of evaluate_baseline_expr does not mutate the variables and thus each
-            let condition = condition.clone();
+    // invocations are independent of each other!
-            let ctx = ctx.clone();
+    scope.enter_scope();
-            ctx.scope.enter_scope();
+    scope.add_vars(&any_args.predicate.captured.entries);
-            ctx.scope.add_vars(&block.captured.entries);
-            ctx.scope.add_var("$it", row);
 
-            let condition = evaluate_baseline_expr(&condition, &*ctx);
+    let result = args.input.fold(init, move |acc, row| {
-            ctx.scope.exit_scope();
+        let condition = condition.clone();
+        let ctx = ctx.clone();
+        if let Some((arg, _)) = any_args.predicate.block.params.positional.first() {
+            ctx.scope.add_var(arg.name(), row);
+        }
 
-            let curr = cond?.drain_vec();
+        let condition = evaluate_baseline_expr(&condition, &ctx);
-            let curr = curr
-                .get(0)
-                .ok_or_else(|| ShellError::unexpected("No value to check with"))?;
-            let cond = curr.as_bool()?;
 
-            match condition {
+        let curr = acc?.drain_vec();
-                Ok(condition) => match condition.as_bool() {
+        let curr = curr
-                    Ok(b) => Ok(InputStream::one(
+            .get(0)
-                        UntaggedValue::boolean(cond || b).into_value(&curr.tag),
+            .ok_or_else(|| ShellError::unexpected("No value to check with"))?;
-                    )),
+        let cond = curr.as_bool()?;
-                    Err(e) => Err(e),
+
-                },
+        match condition {
+            Ok(condition) => match condition.as_bool() {
+                Ok(b) => Ok(InputStream::one(
+                    UntaggedValue::boolean(cond || b).into_value(&curr.tag),
+                )),
                 Err(e) => Err(e),
-            }
+            },
-        })?
+            Err(e) => Err(e),
-        .to_action_stream())
+        }
+    });
+    scope.exit_scope();
+
+    Ok(result?.to_output_stream())
 }
 
 #[cfg(test)]

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

@@ -27,7 +27,7 @@ The .nu-env file has the same format as your $HOME/nu/config.toml file. By loadi
     }
     fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
         Ok(ActionStream::one(ReturnSuccess::value(
-            UntaggedValue::string(get_full_help(&Autoenv, &args.scope)).into_value(Tag::unknown()),
+            UntaggedValue::string(get_full_help(&Autoenv, args.scope())).into_value(Tag::unknown()),
         )))
     }
 

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

@@ -8,6 +8,9 @@ use nu_protocol::hir::{self, Expression, ExternalRedirection, Literal, SpannedEx
 use nu_protocol::{Primitive, Signature, UntaggedValue, Value};
 use nu_table::TextStyle;
 
+#[cfg(feature = "dataframe")]
+use nu_protocol::dataframe::PolarsData;
+
 pub struct Command;
 
 impl WholeStreamCommand for Command {
@@ -43,14 +46,15 @@ impl WholeStreamCommand for Command {
     }
 }
 
-pub fn autoview(context: CommandArgs) -> Result<OutputStream, ShellError> {
+pub fn autoview(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let configuration = context.configs.lock().global_config();
+    let configuration = args.configs().lock().global_config();
+    let tag = args.call_info.name_tag.clone();
 
-    let binary = context.scope.get_command("binaryview");
+    let binary = args.scope().get_command("binaryview");
-    let text = context.scope.get_command("textview");
+    let text = args.scope().get_command("textview");
-    let table = context.scope.get_command("table");
+    let table = args.scope().get_command("table");
-
+    let context = args.context;
-    let (mut input_stream, context) = context.split();
+    let mut input_stream = args.input;
 
     if let Some(x) = input_stream.next() {
         match input_stream.next() {
@@ -62,7 +66,7 @@ pub fn autoview(context: CommandArgs) -> Result<OutputStream, ShellError> {
                 let stream = InputStream::from_stream(xy_stream);
 
                 if let Some(table) = table {
-                    let command_args = create_default_command_args(&context).with_input(stream);
+                    let command_args = create_default_command_args(&context, stream, tag);
                     let result = table.run(command_args)?;
                     let _ = result.collect::<Vec<_>>();
                 }
@@ -74,12 +78,13 @@ pub fn autoview(context: CommandArgs) -> Result<OutputStream, ShellError> {
                         tag: Tag { anchor, span },
                     } if anchor.is_some() => {
                         if let Some(text) = text {
-                            let mut stream = VecDeque::new();
+                            let command_args = create_default_command_args(
-                            stream.push_back(
+                                &context,
-                                UntaggedValue::string(s).into_value(Tag { anchor, span }),
+                                InputStream::one(
+                                    UntaggedValue::string(s).into_value(Tag { anchor, span }),
+                                ),
+                                tag,
                             );
-                            let command_args =
-                                create_default_command_args(&context).with_input(stream);
                             let result = text.run_with_actions(command_args)?;
                             let _ = result.collect::<Vec<_>>();
                         } else {
@@ -104,6 +109,12 @@ pub fn autoview(context: CommandArgs) -> Result<OutputStream, ShellError> {
                     } => {
                         out!("{}", n);
                     }
+                    Value {
+                        value: UntaggedValue::Primitive(Primitive::BigInt(n)),
+                        ..
+                    } => {
+                        out!("{}", n);
+                    }
                     Value {
                         value: UntaggedValue::Primitive(Primitive::Decimal(n)),
                         ..
@@ -158,14 +169,12 @@ pub fn autoview(context: CommandArgs) -> Result<OutputStream, ShellError> {
                         ..
                     } => {
                         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);
+                                create_default_command_args(&context, InputStream::one(x), tag);
                             let result = binary.run_with_actions(command_args)?;
                             let _ = result.collect::<Vec<_>>();
                         } else {
-                            use pretty_hex::*;
+                            use nu_pretty_hex::*;
                             out!("{:?}", b.hex_dump());
                         }
                     }
@@ -220,16 +229,42 @@ pub fn autoview(context: CommandArgs) -> Result<OutputStream, ShellError> {
 
                             println!("{}", nu_table::draw_table(&table, term_width, &color_hm));
                         } else 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);
+                                create_default_command_args(&context, InputStream::one(x), tag);
                             let result = table.run(command_args)?;
                             let _ = result.collect::<Vec<_>>();
                         } else {
                             out!("{:?}", row);
                         }
                     }
+                    #[cfg(feature = "dataframe")]
+                    Value {
+                        value: UntaggedValue::DataFrame(PolarsData::EagerDataFrame(df)),
+                        tag,
+                    } => {
+                        if let Some(table) = table {
+                            // TODO. Configure the parameter rows from file. It can be
+                            // adjusted to see a certain amount of values in the head
+                            let command_args =
+                                create_default_command_args(&context, df.print()?.into(), tag);
+                            let result = table.run(command_args)?;
+                            let _ = result.collect::<Vec<_>>();
+                        }
+                    }
+                    #[cfg(feature = "dataframe")]
+                    Value {
+                        value: UntaggedValue::DataFrame(PolarsData::GroupBy(groupby)),
+                        tag,
+                    } => {
+                        if let Some(table) = table {
+                            // TODO. Configure the parameter rows from file. It can be
+                            // adjusted to see a certain amount of values in the head
+                            let command_args =
+                                create_default_command_args(&context, groupby.print()?.into(), tag);
+                            let result = table.run(command_args)?;
+                            let _ = result.collect::<Vec<_>>();
+                        }
+                    }
                     Value {
                         value: UntaggedValue::Primitive(Primitive::Nothing),
                         ..
@@ -240,10 +275,8 @@ pub fn autoview(context: CommandArgs) -> Result<OutputStream, ShellError> {
                         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);
+                                create_default_command_args(&context, InputStream::one(x), tag);
                             let result = table.run(command_args)?;
                             let _ = result.collect::<Vec<_>>();
                         } else {
@@ -258,14 +291,14 @@ pub fn autoview(context: CommandArgs) -> Result<OutputStream, ShellError> {
     Ok(InputStream::empty())
 }
 
-fn create_default_command_args(context: &RunnableContextWithoutInput) -> RawCommandArgs {
+fn create_default_command_args(
-    let span = context.name.span;
+    context: &EvaluationContext,
-    RawCommandArgs {
+    input: InputStream,
-        host: context.host.clone(),
+    tag: Tag,
-        ctrl_c: context.ctrl_c.clone(),
+) -> CommandArgs {
-        configs: context.configs.clone(),
+    let span = tag.span;
-        current_errors: context.current_errors.clone(),
+    CommandArgs {
-        shell_manager: context.shell_manager.clone(),
+        context: context.clone(),
         call_info: UnevaluatedCallInfo {
             args: hir::Call {
                 head: Box::new(SpannedExpression::new(
@@ -277,9 +310,9 @@ fn create_default_command_args(context: &RunnableContextWithoutInput) -> RawComm
                 span,
                 external_redirection: ExternalRedirection::Stdout,
             },
-            name_tag: context.name.clone(),
+            name_tag: tag,
         },
-        scope: Scope::new(),
+        input,
     }
 }
 

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

@@ -5,7 +5,10 @@ use nu_engine::run_block;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
 use nu_protocol::{
-    hir::{Block, CapturedBlock, ClassifiedCommand, Group, InternalCommand, Pipeline},
+    hir::{
+        Block, CapturedBlock, ClassifiedCommand, ExternalRedirection, Group, InternalCommand,
+        Pipeline,
+    },
     Dictionary, Signature, SyntaxShape, UntaggedValue, Value,
 };
 use rand::{
@@ -47,7 +50,7 @@ impl WholeStreamCommand for Benchmark {
         "Runs a block and returns the time it took to execute it."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         benchmark(args)
     }
 
@@ -67,11 +70,16 @@ impl WholeStreamCommand for Benchmark {
     }
 }
 
-fn benchmark(raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn benchmark(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let tag = raw_args.call_info.args.span;
+    let tag = args.call_info.args.span;
-    let mut context = EvaluationContext::from_args(&raw_args);
+    let mut context = EvaluationContext::from_args(&args);
-    let scope = raw_args.scope.clone();
+    let scope = args.scope().clone();
-    let (BenchmarkArgs { block, passthrough }, input) = raw_args.process()?;
+
+    let args = args.evaluate_once()?;
+    let cmd_args = BenchmarkArgs {
+        block: args.req(0)?,
+        passthrough: args.get_flag("passthrough")?,
+    };
 
     let env = scope.get_env_vars();
     let name = generate_free_name(&env);
@@ -84,7 +92,13 @@ fn benchmark(raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
     // let start = time();
 
     context.scope.enter_scope();
-    let result = run_block(&block.block, &context, input);
+    let result = run_block(
+        &cmd_args.block.block,
+        &context,
+        args.input,
+        ExternalRedirection::StdoutAndStderr,
+    );
+
     context.scope.exit_scope();
     let output = result?.into_vec();
 
@@ -101,7 +115,7 @@ fn benchmark(raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
 
         let real_time = into_big_int(end_time - start_time);
         indexmap.insert("real time".to_string(), real_time);
-        benchmark_output(indexmap, output, passthrough, &tag, &mut context)
+        benchmark_output(indexmap, output, cmd_args.passthrough, &tag, &mut context)
     }
     // return advanced stats
     // #[cfg(feature = "rich-benchmark")]
@@ -134,10 +148,10 @@ fn benchmark_output<T, Output>(
     passthrough: Option<CapturedBlock>,
     tag: T,
     context: &mut EvaluationContext,
-) -> Result<ActionStream, ShellError>
+) -> Result<OutputStream, ShellError>
 where
     T: Into<Tag> + Copy,
-    Output: Into<ActionStream>,
+    Output: Into<OutputStream>,
 {
     let value = UntaggedValue::Row(Dictionary::from(
         indexmap
@@ -154,14 +168,19 @@ where
         let time_block = add_implicit_autoview(time_block.block);
 
         context.scope.enter_scope();
-        let result = run_block(&time_block, context, benchmark_output);
+        let result = run_block(
+            &time_block,
+            context,
+            benchmark_output,
+            ExternalRedirection::StdoutAndStderr,
+        );
         context.scope.exit_scope();
         result?;
         context.clear_errors();
 
         Ok(block_output.into())
     } else {
-        let benchmark_output = ActionStream::one(value);
+        let benchmark_output = OutputStream::one(value);
         Ok(benchmark_output)
     }
 }

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

@@ -3,7 +3,7 @@ use nu_errors::ShellError;
 
 use nu_data::value::format_leaf;
 use nu_engine::WholeStreamCommand;
-use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_protocol::{Signature, SyntaxShape, UntaggedValue, Value};
 
 pub struct BuildString;
 
@@ -21,7 +21,7 @@ impl WholeStreamCommand for BuildString {
         "Builds a string from the arguments."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         let tag = args.call_info.name_tag.clone();
         let args = args.evaluate_once()?;
         let rest: Vec<Value> = args.rest(0)?;
@@ -32,9 +32,9 @@ impl WholeStreamCommand for BuildString {
             output_string.push_str(&format_leaf(&r).plain_string(100_000))
         }
 
-        Ok(ActionStream::one(ReturnSuccess::value(
+        Ok(OutputStream::one(
             UntaggedValue::string(output_string).into_value(tag),
-        )))
+        ))
     }
 
     fn examples(&self) -> Vec<Example> {

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

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 use chrono::{Datelike, Local, NaiveDate};
 use indexmap::IndexMap;
-use nu_engine::{EvaluatedWholeStreamCommandArgs, WholeStreamCommand};
+use nu_engine::{EvaluatedCommandArgs, WholeStreamCommand};
 use nu_errors::ShellError;
 use nu_protocol::{Dictionary, Signature, SyntaxShape, UntaggedValue, Value};
 
@@ -165,7 +165,7 @@ fn get_current_date() -> (i32, u32, u32) {
 }
 
 fn add_months_of_year_to_table(
-    args: &EvaluatedWholeStreamCommandArgs,
+    args: &EvaluatedCommandArgs,
     mut calendar_vec_deque: &mut VecDeque<Value>,
     tag: &Tag,
     selected_year: i32,
@@ -198,7 +198,7 @@ fn add_months_of_year_to_table(
 }
 
 fn add_month_to_table(
-    args: &EvaluatedWholeStreamCommandArgs,
+    args: &EvaluatedCommandArgs,
     calendar_vec_deque: &mut VecDeque<Value>,
     tag: &Tag,
     selected_year: i32,

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

@@ -26,7 +26,7 @@ impl WholeStreamCommand for Cd {
 
     fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
         let name = args.call_info.name_tag.clone();
-        let shell_manager = args.shell_manager.clone();
+        let shell_manager = args.shell_manager();
         let (args, _): (CdArgs, _) = args.process()?;
         shell_manager.cd(args, name)
     }

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

@@ -1,11 +1,108 @@
 use crate::prelude::*;
 use nu_engine::{FromValue, WholeStreamCommand};
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_protocol::{Signature, SyntaxShape, TaggedDictBuilder, UntaggedValue, Value};
 use nu_source::Tagged;
 
+use indexmap::indexmap;
+use indexmap::map::IndexMap;
+use lazy_static::lazy_static;
+
 pub struct Char;
 
+struct CharArgs {
+    name: Option<Tagged<String>>,
+    rest: Vec<Value>,
+    list: bool,
+    unicode: bool,
+}
+
+lazy_static! {
+    static ref CHAR_MAP: IndexMap<&'static str, String> = indexmap! {
+        // These are some regular characters that either can't used or
+        // it's just easier to use them like this.
+        "newline" => '\n'.to_string(),
+        "enter" => '\n'.to_string(),
+        "nl" => '\n'.to_string(),
+        "tab" => '\t'.to_string(),
+        "sp" => ' '.to_string(),
+        "space" => ' '.to_string(),
+        "pipe" => '|'.to_string(),
+        "left_brace" => '{'.to_string(),
+        "lbrace" => '{'.to_string(),
+        "right_brace" => '}'.to_string(),
+        "rbrace" => '}'.to_string(),
+        "left_paren" => '('.to_string(),
+        "lparen" => '('.to_string(),
+        "right_paren" => ')'.to_string(),
+        "rparen" => ')'.to_string(),
+        "left_bracket" => '['.to_string(),
+        "lbracket" => '['.to_string(),
+        "right_bracket" => ']'.to_string(),
+        "rbracket" => ']'.to_string(),
+        "sep" => std::path::MAIN_SEPARATOR.to_string(),
+        "separator" => std::path::MAIN_SEPARATOR.to_string(),
+
+        // Unicode names came from https://www.compart.com/en/unicode
+        // Private Use Area (U+E000-U+F8FF)
+        // Unicode can't be mixed with Ansi or it will break width calculation
+        "branch" => '\u{e0a0}'.to_string(),                        // 
+        "segment" => '\u{e0b0}'.to_string(),                       // 
+
+        "identical_to" => '\u{2261}'.to_string(),                  // ≡
+        "hamburger" => '\u{2261}'.to_string(),                     // ≡
+        "not_identical_to" => '\u{2262}'.to_string(),              // ≢
+        "branch_untracked" => '\u{2262}'.to_string(),              // ≢
+        "strictly_equivalent_to" => '\u{2263}'.to_string(),        // ≣
+        "branch_identical" => '\u{2263}'.to_string(),              // ≣
+
+        "upwards_arrow" => '\u{2191}'.to_string(),                 // ↑
+        "branch_ahead" => '\u{2191}'.to_string(),                  // ↑
+        "downwards_arrow" => '\u{2193}'.to_string(),               // ↓
+        "branch_behind" => '\u{2193}'.to_string(),                 // ↓
+        "up_down_arrow" => '\u{2195}'.to_string(),                 // ↕
+        "branch_ahead_behind" => '\u{2195}'.to_string(),           // ↕
+
+        "black_right_pointing_triangle" => '\u{25b6}'.to_string(), // ▶
+        "prompt" => '\u{25b6}'.to_string(),                        // ▶
+        "vector_or_cross_product" => '\u{2a2f}'.to_string(),       // ⨯
+        "failed" => '\u{2a2f}'.to_string(),                        // ⨯
+        "high_voltage_sign" => '\u{26a1}'.to_string(),             // ⚡
+        "elevated" => '\u{26a1}'.to_string(),                      // ⚡
+        "tilde" => '~'.to_string(),                                // ~
+        "twiddle" => '~'.to_string(),                              // ~
+        "squiggly" => '~'.to_string(),                             // ~
+        "home" => '~'.to_string(),                                 // ~
+        "hash" => '#'.to_string(),                                 // #
+        "hashtag" => '#'.to_string(),                              // #
+        "pound_sign" => '#'.to_string(),                           // #
+        "sharp" => '#'.to_string(),                                // #
+        "root" => '#'.to_string(),                                 // #
+
+        // Weather symbols
+        "sun" => "☀️".to_string(),
+        "sunny" => "☀️".to_string(),
+        "sunrise" => "☀️".to_string(),
+        "moon" => "🌛".to_string(),
+        "cloudy" => "☁️".to_string(),
+        "cloud" => "☁️".to_string(),
+        "clouds" => "☁️".to_string(),
+        "rainy" => "🌦️".to_string(),
+        "rain" => "🌦️".to_string(),
+        "foggy" => "🌫️".to_string(),
+        "fog" => "🌫️".to_string(),
+        "mist" => '\u{2591}'.to_string(),
+        "haze" => '\u{2591}'.to_string(),
+        "snowy" => "❄️".to_string(),
+        "snow" => "❄️".to_string(),
+        "thunderstorm" => "🌩️".to_string(),
+        "thunder" => "🌩️".to_string(),
+
+        "bel" => '\x07'.to_string(),       // Terminal Bell
+        "backspace" => '\x08'.to_string(), // Backspace
+    };
+}
+
 impl WholeStreamCommand for Char {
     fn name(&self) -> &str {
         "char"
@@ -13,17 +110,18 @@ impl WholeStreamCommand for Char {
 
     fn signature(&self) -> Signature {
         Signature::build("char")
-            .required(
+            .optional(
                 "character",
                 SyntaxShape::Any,
                 "the name of the character to output",
             )
             .rest(SyntaxShape::String, "multiple Unicode bytes")
+            .switch("list", "List all supported character names", Some('l'))
             .switch("unicode", "Unicode string i.e. 1f378", Some('u'))
     }
 
     fn usage(&self) -> &str {
-        "Output special characters (eg. 'newline')."
+        "Output special characters (e.g., 'newline')."
     }
 
     fn examples(&self) -> Vec<Example> {
@@ -35,7 +133,7 @@ impl WholeStreamCommand for Char {
             },
             Example {
                 description: "Output prompt character, newline and a hamburger character",
-                example: r#"echo $(char prompt) $(char newline) $(char hamburger)"#,
+                example: r#"echo (char prompt) (char newline) (char hamburger)"#,
                 result: Some(vec![
                     UntaggedValue::string("\u{25b6}").into(),
                     UntaggedValue::string("\n").into(),
@@ -57,62 +155,86 @@ impl WholeStreamCommand for Char {
         ]
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        let args_tag = args.call_info.name_tag.clone();
         let args = args.evaluate_once()?;
+        let args = CharArgs {
+            name: args.opt(0)?,
+            rest: args.rest(1)?,
+            list: args.has_flag("list"),
+            unicode: args.has_flag("unicode"),
+        };
 
-        let name: Tagged<String> = args.req(0)?;
+        if args.list {
-        let rest: Vec<Value> = args.rest(1)?;
+            Ok(CHAR_MAP
-        let unicode = args.has_flag("unicode");
+                .iter()
-
+                .map(move |(name, s)| {
-        if unicode {
+                    let mut dict = TaggedDictBuilder::with_capacity(&args_tag, 2);
-            if !rest.is_empty() {
+                    dict.insert_untagged("name", UntaggedValue::string(*name));
-                // Setup a new buffer to put all the Unicode bytes in
+                    dict.insert_untagged("character", UntaggedValue::string(s));
-                let mut multi_byte = String::new();
+                    let unicode_parts: Vec<String> =
-                // Get the first byte
+                        s.chars().map(|c| format!("{:x}", c as u32)).collect();
-                let decoded_char = string_to_unicode_char(&name.item, &name.tag);
+                    dict.insert_untagged("unicode", UntaggedValue::string(unicode_parts.join(" ")));
-                match decoded_char {
+                    dict.into_value()
-                    Ok(ch) => multi_byte.push(ch),
+                })
-                    Err(e) => return Err(e),
+                .to_output_stream())
-                }
+        } else if let Some(name) = args.name {
-                // Get the rest of the bytes
+            if args.unicode {
-                for byte_part in rest {
+                if !args.rest.is_empty() {
-                    let byte_part: Tagged<String> = FromValue::from_value(&byte_part)?;
+                    // Setup a new buffer to put all the Unicode bytes in
-                    let decoded_char = string_to_unicode_char(&byte_part, &byte_part.tag);
+                    let mut multi_byte = String::new();
+                    // Get the first byte
+                    let decoded_char = string_to_unicode_char(&name.item, &name.tag);
                     match decoded_char {
                         Ok(ch) => multi_byte.push(ch),
                         Err(e) => return Err(e),
                     }
+                    // Get the rest of the bytes
+                    for byte_part in args.rest {
+                        let byte_part: Tagged<String> = FromValue::from_value(&byte_part)?;
+                        let decoded_char = string_to_unicode_char(&byte_part, &byte_part.tag);
+                        match decoded_char {
+                            Ok(ch) => multi_byte.push(ch),
+                            Err(e) => return Err(e),
+                        }
+                    }
+                    Ok(OutputStream::one(
+                        UntaggedValue::string(multi_byte).into_value(name.tag),
+                    ))
+                } else {
+                    let decoded_char = string_to_unicode_char(&name.item, &name.tag);
+                    if let Ok(ch) = decoded_char {
+                        Ok(OutputStream::one(
+                            UntaggedValue::string(ch).into_value(name.tag()),
+                        ))
+                    } else {
+                        Err(ShellError::labeled_error(
+                            "error decoding Unicode character",
+                            "error decoding Unicode character",
+                            name.tag(),
+                        ))
+                    }
                 }
-                Ok(ActionStream::one(ReturnSuccess::value(
-                    UntaggedValue::string(multi_byte).into_value(name.tag),
-                )))
             } else {
-                let decoded_char = string_to_unicode_char(&name.item, &name.tag);
+                let special_character = str_to_character(&name.item);
-                if let Ok(ch) = decoded_char {
+                if let Some(output) = special_character {
-                    Ok(ActionStream::one(ReturnSuccess::value(
+                    Ok(OutputStream::one(
-                        UntaggedValue::string(ch).into_value(name.tag()),
+                        UntaggedValue::string(output).into_value(name.tag()),
-                    )))
+                    ))
                 } else {
                     Err(ShellError::labeled_error(
-                        "error decoding Unicode character",
+                        "error finding named character",
-                        "error decoding Unicode character",
+                        "error finding named character",
                         name.tag(),
                     ))
                 }
             }
         } else {
-            let special_character = str_to_character(&name.item);
+            Err(ShellError::labeled_error(
-            if let Some(output) = special_character {
+                "char requires the name of the character",
-                Ok(ActionStream::one(ReturnSuccess::value(
+                "missing name of the character",
-                    UntaggedValue::string(output).into_value(name.tag()),
+                &args_tag,
-                )))
+            ))
-            } else {
-                Err(ShellError::labeled_error(
-                    "error finding named character",
-                    "error finding named character",
-                    name.tag(),
-                ))
-            }
         }
     }
 }
@@ -134,45 +256,7 @@ fn string_to_unicode_char(s: &str, t: &Tag) -> Result<char, ShellError> {
 }
 
 fn str_to_character(s: &str) -> Option<String> {
-    match s {
+    CHAR_MAP.get(s).map(|s| s.into())
-        "newline" | "enter" | "nl" => Some("\n".into()),
-        "tab" => Some("\t".into()),
-        "sp" | "space" => Some(" ".into()),
-        // Unicode names came from https://www.compart.com/en/unicode
-        // Private Use Area (U+E000-U+F8FF)
-        // Unicode can't be mixed with Ansi or it will break width calculation
-        "branch" => Some('\u{e0a0}'.to_string()),  // 
-        "segment" => Some('\u{e0b0}'.to_string()), // 
-
-        "identical_to" | "hamburger" => Some('\u{2261}'.to_string()), // ≡
-        "not_identical_to" | "branch_untracked" => Some('\u{2262}'.to_string()), // ≢
-        "strictly_equivalent_to" | "branch_identical" => Some('\u{2263}'.to_string()), // ≣
-
-        "upwards_arrow" | "branch_ahead" => Some('\u{2191}'.to_string()), // ↑
-        "downwards_arrow" | "branch_behind" => Some('\u{2193}'.to_string()), // ↓
-        "up_down_arrow" | "branch_ahead_behind" => Some('\u{2195}'.to_string()), // ↕
-
-        "black_right_pointing_triangle" | "prompt" => Some('\u{25b6}'.to_string()), // ▶
-        "vector_or_cross_product" | "failed" => Some('\u{2a2f}'.to_string()),       // ⨯
-        "high_voltage_sign" | "elevated" => Some('\u{26a1}'.to_string()),           // ⚡
-        "tilde" | "twiddle" | "squiggly" | "home" => Some("~".into()),              // ~
-        "hash" | "hashtag" | "pound_sign" | "sharp" | "root" => Some("#".into()),   // #
-
-        // Weather symbols
-        "sun" | "sunny" | "sunrise" => Some("☀️".to_string()),
-        "moon" => Some("🌛".to_string()),
-        "cloudy" | "cloud" | "clouds" => Some("☁️".to_string()),
-        "rainy" | "rain" => Some("🌦️".to_string()),
-        "foggy" | "fog" => Some("🌫️".to_string()),
-        "mist" | "haze" => Some("\u{2591}".to_string()),
-        "snowy" | "snow" => Some("❄️".to_string()),
-        "thunderstorm" | "thunder" => Some("🌩️".to_string()),
-
-        "bel" => Some('\x07'.to_string()),       // Terminal Bell
-        "backspace" => Some('\x08'.to_string()), // Backspace
-
-        _ => None,
-    }
 }
 
 #[cfg(test)]

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

@@ -20,14 +20,14 @@ impl WholeStreamCommand for Chart {
     }
 
     fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
-        if args.scope.get_command("chart bar").is_none() {
+        if args.scope().get_command("chart bar").is_none() {
             return Err(ShellError::untagged_runtime_error(
                 "nu_plugin_chart not installed.",
             ));
         }
 
         Ok(ActionStream::one(Ok(ReturnSuccess::Value(
-            UntaggedValue::string(get_full_help(&Chart, &args.scope)).into_value(Tag::unknown()),
+            UntaggedValue::string(get_full_help(&Chart, args.scope())).into_value(Tag::unknown()),
         ))))
     }
 }

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

@@ -1,6 +1,7 @@
 use crate::prelude::*;
 use nu_engine::{evaluate_baseline_expr, BufCodecReader};
 use nu_engine::{MaybeTextCodec, StringOrBinary};
+use nu_test_support::NATIVE_PATH_ENV_VAR;
 use parking_lot::Mutex;
 
 use std::io::Write;
@@ -149,7 +150,9 @@ fn spawn(
             process.arg(&command.name);
             for arg in args {
                 // Clean the args before we use them:
-                let arg = arg.replace("|", "\\|");
+                // https://stackoverflow.com/questions/1200235/how-to-pass-a-quoted-pipe-character-to-cmd-exe
+                // cmd.exe needs to have a caret to escape a pipe
+                let arg = arg.replace("|", "^|");
                 process.arg(&arg);
             }
             process
@@ -199,247 +202,250 @@ fn spawn(
     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() {
+    match process.spawn() {
-        let (tx, rx) = mpsc::sync_channel(0);
+        Ok(mut child) => {
+            let (tx, rx) = mpsc::sync_channel(0);
 
-        let mut stdin = child.stdin.take();
+            let mut stdin = child.stdin.take();
 
-        let stdin_write_tx = tx.clone();
+            let stdin_write_tx = tx.clone();
-        let stdout_read_tx = tx;
+            let stdout_read_tx = tx;
-        let stdin_name_tag = command.name_tag.clone();
+            let stdin_name_tag = command.name_tag.clone();
-        let stdout_name_tag = command.name_tag;
+            let stdout_name_tag = command.name_tag;
 
-        std::thread::spawn(move || {
+            std::thread::spawn(move || {
-            if !input.is_empty() {
+                if !input.is_empty() {
-                let mut stdin_write = stdin
+                    let mut stdin_write = stdin
-                    .take()
+                        .take()
-                    .expect("Internal error: could not get stdin pipe for external command");
+                        .expect("Internal error: could not get stdin pipe for external command");
 
-                for value in input {
+                    for value in input {
-                    match &value.value {
+                        match &value.value {
-                        UntaggedValue::Primitive(Primitive::Nothing) => continue,
+                            UntaggedValue::Primitive(Primitive::Nothing) => continue,
-                        UntaggedValue::Primitive(Primitive::String(s)) => {
+                            UntaggedValue::Primitive(Primitive::String(s)) => {
-                            if stdin_write.write(s.as_bytes()).is_err() {
+                                if stdin_write.write(s.as_bytes()).is_err() {
-                                // Other side has closed, so exit
+                                    // Other side has closed, so exit
-                                return Ok(());
+                                    return Ok(());
-                            }
-                        }
-                        UntaggedValue::Primitive(Primitive::Binary(b)) => {
-                            if stdin_write.write(b).is_err() {
-                                // Other side has closed, so exit
-                                return Ok(());
-                            }
-                        }
-                        unsupported => {
-                            println!("Unsupported: {:?}", 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 external_redirection == ExternalRedirection::Stdout
-                || external_redirection == ExternalRedirection::StdoutAndStderr
-            {
-                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::default());
-                let buf_read = BufReader::new(stdout);
-                let buf_codec = BufCodecReader::new(buf_read, MaybeTextCodec::default());
-
-                for line in buf_codec {
-                    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) => {
+                            UntaggedValue::Primitive(Primitive::Binary(b)) => {
-                                let result = stdout_read_tx.send(Ok(Value {
+                                if stdin_write.write(b).is_err() {
-                                    value: UntaggedValue::Primitive(Primitive::Binary(
+                                    // Other side has closed, so exit
-                                        b.into_iter().collect(),
+                                    return Ok(());
-                                    )),
-                                    tag: stdout_name_tag.clone(),
-                                }));
-
-                                if result.is_err() {
-                                    break;
                                 }
                             }
-                        },
+                            unsupported => {
-                        Err(e) => {
+                                println!("Unsupported: {:?}", unsupported);
-                            // If there's an exit status, it makes sense that we may error when
+                                let _ = stdin_write_tx.send(Ok(Value {
-                            // trying to read from its stdout pipe (likely been closed). In that
-                            // case, don't emit an error.
-                            let should_error = match child.wait() {
-                                Ok(exit_status) => !exit_status.success(),
-                                Err(_) => true,
-                            };
-
-                            if should_error {
-                                let _ = stdout_read_tx.send(Ok(Value {
                                     value: UntaggedValue::Error(ShellError::labeled_error(
-                                        format!("Unable to read from stdout ({})", e),
+                                        format!(
-                                        "unable to read from stdout",
+                                            "Received unexpected type from pipeline ({})",
-                                        &stdout_name_tag,
+                                            unsupported.type_name()
+                                        ),
+                                        "expected a string",
+                                        stdin_name_tag.clone(),
                                     )),
-                                    tag: stdout_name_tag.clone(),
+                                    tag: stdin_name_tag,
                                 }));
+                                return Err(());
                             }
-
+                        };
-                            return Ok(());
-                        }
                     }
                 }
-            }
-            if external_redirection == ExternalRedirection::Stderr
-                || external_redirection == ExternalRedirection::StdoutAndStderr
-            {
-                let stderr = if let Some(stderr) = child.stderr.take() {
-                    stderr
-                } else {
-                    let _ = stdout_read_tx.send(Ok(Value {
-                        value: UntaggedValue::Error(ShellError::labeled_error(
-                            "Can't redirect the stderr for external command",
-                            "can't redirect stderr",
-                            &stdout_name_tag,
-                        )),
-                        tag: stdout_name_tag,
-                    }));
-                    return Err(());
-                };
 
-                // let file = futures::io::AllowStdIo::new(stderr);
+                Ok(())
-                // let stream = FramedRead::new(file, MaybeTextCodec::default());
+            });
-                let buf_reader = BufReader::new(stderr);
-                let buf_codec = BufCodecReader::new(buf_reader, MaybeTextCodec::default());
 
-                for line in buf_codec {
+            std::thread::spawn(move || {
-                    match line {
+                if external_redirection == ExternalRedirection::Stdout
-                        Ok(line) => match line {
+                    || external_redirection == ExternalRedirection::StdoutAndStderr
-                            StringOrBinary::String(s) => {
+                {
-                                let result = stdout_read_tx.send(Ok(Value {
+                    let stdout = if let Some(stdout) = child.stdout.take() {
-                                    value: UntaggedValue::Error(
+                        stdout
-                                        ShellError::untagged_runtime_error(s),
+                    } else {
-                                    ),
-                                    tag: stdout_name_tag.clone(),
-                                }));
-
-                                if result.is_err() {
-                                    break;
-                                }
-                            }
-                            StringOrBinary::Binary(_) => {
-                                let result = stdout_read_tx.send(Ok(Value {
-                                    value: UntaggedValue::Error(
-                                        ShellError::untagged_runtime_error("<binary stderr>"),
-                                    ),
-                                    tag: stdout_name_tag.clone(),
-                                }));
-
-                                if result.is_err() {
-                                    break;
-                                }
-                            }
-                        },
-                        Err(e) => {
-                            // If there's an exit status, it makes sense that we may error when
-                            // trying to read from its stdout pipe (likely been closed). In that
-                            // case, don't emit an error.
-                            let should_error = match child.wait() {
-                                Ok(exit_status) => !exit_status.success(),
-                                Err(_) => true,
-                            };
-
-                            if should_error {
-                                let _ = stdout_read_tx.send(Ok(Value {
-                                    value: UntaggedValue::Error(ShellError::labeled_error(
-                                        format!("Unable to read from stdout ({})", e),
-                                        "unable to read from stdout",
-                                        &stdout_name_tag,
-                                    )),
-                                    tag: stdout_name_tag.clone(),
-                                }));
-                            }
-
-                            return Ok(());
-                        }
-                    }
-                }
-            }
-
-            // We can give an error when we see a non-zero exit code, but this is different
-            // than what other shells will do.
-            let external_failed = match child.wait() {
-                Err(_) => true,
-                Ok(exit_status) => !exit_status.success(),
-            };
-
-            if external_failed {
-                let cfg = nu_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",
+                                "Can't redirect the stdout for external command",
-                                "command failed",
+                                "can't redirect stdout",
                                 &stdout_name_tag,
                             )),
-                            tag: stdout_name_tag.clone(),
+                            tag: stdout_name_tag,
                         }));
+                        return Err(());
+                    };
+
+                    // let file = futures::io::AllowStdIo::new(stdout);
+                    // let stream = FramedRead::new(file, MaybeTextCodec::default());
+                    let buf_read = BufReader::new(stdout);
+                    let buf_codec = BufCodecReader::new(buf_read, MaybeTextCodec::default());
+
+                    for line in buf_codec {
+                        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(e) => {
+                                // If there's an exit status, it makes sense that we may error when
+                                // trying to read from its stdout pipe (likely been closed). In that
+                                // case, don't emit an error.
+                                let should_error = match child.wait() {
+                                    Ok(exit_status) => !exit_status.success(),
+                                    Err(_) => true,
+                                };
+
+                                if should_error {
+                                    let _ = stdout_read_tx.send(Ok(Value {
+                                        value: UntaggedValue::Error(ShellError::labeled_error(
+                                            format!("Unable to read from stdout ({})", e),
+                                            "unable to read from stdout",
+                                            &stdout_name_tag,
+                                        )),
+                                        tag: stdout_name_tag.clone(),
+                                    }));
+                                }
+
+                                return Ok(());
+                            }
+                        }
                     }
                 }
-                let _ = stdout_read_tx.send(Ok(Value {
+                if external_redirection == ExternalRedirection::Stderr
-                    value: UntaggedValue::Error(ShellError::external_non_zero()),
+                    || external_redirection == ExternalRedirection::StdoutAndStderr
-                    tag: stdout_name_tag,
+                {
-                }));
+                    let stderr = if let Some(stderr) = child.stderr.take() {
-            }
+                        stderr
+                    } else {
+                        let _ = stdout_read_tx.send(Ok(Value {
+                            value: UntaggedValue::Error(ShellError::labeled_error(
+                                "Can't redirect the stderr for external command",
+                                "can't redirect stderr",
+                                &stdout_name_tag,
+                            )),
+                            tag: stdout_name_tag,
+                        }));
+                        return Err(());
+                    };
 
-            Ok(())
+                    // let file = futures::io::AllowStdIo::new(stderr);
-        });
+                    // let stream = FramedRead::new(file, MaybeTextCodec::default());
+                    let buf_reader = BufReader::new(stderr);
+                    let buf_codec = BufCodecReader::new(buf_reader, MaybeTextCodec::default());
 
-        let stream = ChannelReceiver::new(rx);
+                    for line in buf_codec {
-        Ok(stream.to_input_stream())
+                        match line {
-    } else {
+                            Ok(line) => match line {
-        Err(ShellError::labeled_error(
+                                StringOrBinary::String(s) => {
-            "Failed to spawn process",
+                                    let result = stdout_read_tx.send(Ok(Value {
+                                        value: UntaggedValue::Error(
+                                            ShellError::untagged_runtime_error(s),
+                                        ),
+                                        tag: stdout_name_tag.clone(),
+                                    }));
+
+                                    if result.is_err() {
+                                        break;
+                                    }
+                                }
+                                StringOrBinary::Binary(_) => {
+                                    let result = stdout_read_tx.send(Ok(Value {
+                                        value: UntaggedValue::Error(
+                                            ShellError::untagged_runtime_error("<binary stderr>"),
+                                        ),
+                                        tag: stdout_name_tag.clone(),
+                                    }));
+
+                                    if result.is_err() {
+                                        break;
+                                    }
+                                }
+                            },
+                            Err(e) => {
+                                // If there's an exit status, it makes sense that we may error when
+                                // trying to read from its stdout pipe (likely been closed). In that
+                                // case, don't emit an error.
+                                let should_error = match child.wait() {
+                                    Ok(exit_status) => !exit_status.success(),
+                                    Err(_) => true,
+                                };
+
+                                if should_error {
+                                    let _ = stdout_read_tx.send(Ok(Value {
+                                        value: UntaggedValue::Error(ShellError::labeled_error(
+                                            format!("Unable to read from stdout ({})", e),
+                                            "unable to read from stdout",
+                                            &stdout_name_tag,
+                                        )),
+                                        tag: stdout_name_tag.clone(),
+                                    }));
+                                }
+
+                                return Ok(());
+                            }
+                        }
+                    }
+                }
+
+                // We can give an error when we see a non-zero exit code, but this is different
+                // than what other shells will do.
+                let external_failed = match child.wait() {
+                    Err(_) => true,
+                    Ok(exit_status) => !exit_status.success(),
+                };
+
+                if external_failed {
+                    let cfg = nu_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.clone(),
+                            }));
+                        }
+                    }
+                    let _ = stdout_read_tx.send(Ok(Value {
+                        value: UntaggedValue::Error(ShellError::external_non_zero()),
+                        tag: stdout_name_tag,
+                    }));
+                }
+
+                Ok(())
+            });
+
+            let stream = ChannelReceiver::new(rx);
+            Ok(stream.to_input_stream())
+        }
+        Err(e) => Err(ShellError::labeled_error(
+            format!("{}", e),
             "failed to spawn",
             &command.name_tag,
-        ))
+        )),
     }
 }
 
@@ -515,7 +521,7 @@ fn remove_quotes(argument: &str) -> Option<&str> {
 fn shell_os_paths() -> Vec<std::path::PathBuf> {
     let mut original_paths = vec![];
 
-    if let Some(paths) = std::env::var_os("PATH") {
+    if let Some(paths) = std::env::var_os(NATIVE_PATH_ENV_VAR) {
         original_paths = std::env::split_paths(&paths).collect::<Vec<_>>();
     }
 
@@ -531,7 +537,7 @@ mod tests {
     use super::{run_external_command, InputStream};
 
     #[cfg(feature = "which")]
-    use nu_engine::basic_evaluation_context;
+    use nu_engine::EvaluationContext;
 
     #[cfg(feature = "which")]
     use nu_test_support::commands::ExternalBuilder;
@@ -554,8 +560,7 @@ mod tests {
         let cmd = ExternalBuilder::for_name("i_dont_exist.exe").build();
 
         let input = InputStream::empty();
-        let mut ctx =
+        let mut ctx = EvaluationContext::basic();
-            basic_evaluation_context().expect("There was a problem creating a basic context.");
 
         assert!(run_external_command(cmd, &mut ctx, input, ExternalRedirection::Stdout).is_err());
     }
@@ -563,7 +568,7 @@ mod tests {
     // fn failure_run() -> Result<(), ShellError> {
     //     let cmd = ExternalBuilder::for_name("fail").build();
 
-    //     let mut ctx = crate::cli::basic_evaluation_context().expect("There was a problem creating a basic context.");
+    //     let mut ctx = crate::cli::EvaluationContext::basic().expect("There was a problem creating a basic context.");
     //     let stream = run_external_command(cmd, &mut ctx, None, false)
     //         ?
     //         .expect("There was a problem running the external command.");

crates/nu-command/src/commands/config/clear.rs

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, Signature, UntaggedValue};
+use nu_protocol::{Signature, UntaggedValue};
 
 pub struct SubCommand;
 
@@ -18,7 +18,7 @@ impl WholeStreamCommand for SubCommand {
         "clear the config"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         clear(args)
     }
 
@@ -31,22 +31,22 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-pub fn clear(args: CommandArgs) -> Result<ActionStream, ShellError> {
+pub fn clear(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let name = args.call_info.name_tag.clone();
     let ctx = EvaluationContext::from_args(&args);
 
-    let result = if let Some(global_cfg) = &mut args.configs.lock().global_config {
+    let result = if let Some(global_cfg) = &mut args.configs().lock().global_config {
         global_cfg.vars.clear();
         global_cfg.write()?;
         ctx.reload_config(global_cfg)?;
-        Ok(ActionStream::one(ReturnSuccess::value(
+
-            UntaggedValue::Row(global_cfg.vars.clone().into()).into_value(args.call_info.name_tag),
+        let value = UntaggedValue::Row(global_cfg.vars.clone().into()).into_value(name);
-        )))
+        Ok(OutputStream::one(value))
     } else {
-        Ok(vec![ReturnSuccess::value(UntaggedValue::Error(
+        let value = UntaggedValue::Error(crate::commands::config::err_no_global_cfg_present())
-            crate::commands::config::err_no_global_cfg_present(),
+            .into_value(name);
-        ))]
+
-        .into_iter()
+        Ok(OutputStream::one(value))
-        .to_action_stream())
     };
 
     result

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

@@ -2,8 +2,7 @@ use crate::prelude::*;
 use nu_engine::CommandArgs;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, Signature, UntaggedValue};
+use nu_protocol::{Signature, UntaggedValue};
-use nu_stream::ActionStream;
 
 pub struct Command;
 
@@ -20,22 +19,19 @@ impl WholeStreamCommand for Command {
         "Configuration management."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
-        let name = args.call_info.name_tag;
+        let name = args.call_info.name_tag.clone();
 
-        if let Some(global_cfg) = &args.configs.lock().global_config {
+        if let Some(global_cfg) = &args.configs().lock().global_config {
             let result = global_cfg.vars.clone();
-            Ok(vec![ReturnSuccess::value(
+            let value = UntaggedValue::Row(result.into()).into_value(name);
-                UntaggedValue::Row(result.into()).into_value(name),
+
-            )]
+            Ok(OutputStream::one(value))
-            .into_iter()
-            .to_action_stream())
         } else {
-            Ok(vec![ReturnSuccess::value(UntaggedValue::Error(
+            let value = UntaggedValue::Error(crate::commands::config::err_no_global_cfg_present())
-                crate::commands::config::err_no_global_cfg_present(),
+                .into_value(name);
-            ))]
+
-            .into_iter()
+            Ok(OutputStream::one(value))
-            .to_action_stream())
         }
     }
 }

crates/nu-command/src/commands/config/get.rs

@@ -1,15 +1,10 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ColumnPath, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_protocol::{Signature, SyntaxShape, UntaggedValue, Value};
 
 pub struct SubCommand;
 
-#[derive(Deserialize)]
-pub struct Arguments {
-    column_path: ColumnPath,
-}
-
 impl WholeStreamCommand for SubCommand {
     fn name(&self) -> &str {
         "config get"
@@ -27,7 +22,7 @@ impl WholeStreamCommand for SubCommand {
         "Gets a value from the config"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         get(args)
     }
 
@@ -40,11 +35,12 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-pub fn get(args: CommandArgs) -> Result<ActionStream, ShellError> {
+pub fn get(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let name = args.call_info.name_tag.clone();
     let ctx = EvaluationContext::from_args(&args);
+    let args = args.evaluate_once()?;
 
-    let (Arguments { column_path }, _) = args.process()?;
+    let column_path = args.req(0)?;
 
     let result = if let Some(global_cfg) = &ctx.configs.lock().global_config {
         let result = UntaggedValue::row(global_cfg.vars.clone()).into_value(&name);
@@ -53,15 +49,14 @@ pub fn get(args: CommandArgs) -> Result<ActionStream, ShellError> {
             Value {
                 value: UntaggedValue::Table(list),
                 ..
-            } => list.into_iter().to_action_stream(),
+            } => OutputStream::from_stream(list.into_iter()),
-            x => ActionStream::one(ReturnSuccess::value(x)),
+            x => OutputStream::one(x),
         })
     } else {
-        Ok(vec![ReturnSuccess::value(UntaggedValue::Error(
+        let value = UntaggedValue::Error(crate::commands::config::err_no_global_cfg_present())
-            crate::commands::config::err_no_global_cfg_present(),
+            .into_value(name);
-        ))]
+
-        .into_iter()
+        Ok(OutputStream::one(value))
-        .to_action_stream())
     };
 
     result

crates/nu-command/src/commands/config/path.rs

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{Primitive, ReturnSuccess, Signature, UntaggedValue};
+use nu_protocol::{Primitive, Signature, UntaggedValue};
 
 pub struct SubCommand;
 
@@ -18,7 +18,7 @@ impl WholeStreamCommand for SubCommand {
         "return the path to the config file"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         path(args)
     }
 
@@ -31,16 +31,18 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-pub fn path(args: CommandArgs) -> Result<ActionStream, ShellError> {
+pub fn path(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    if let Some(global_cfg) = &mut args.configs.lock().global_config {
+    let name = args.call_info.name_tag.clone();
-        Ok(ActionStream::one(ReturnSuccess::value(
+
-            UntaggedValue::Primitive(Primitive::FilePath(global_cfg.file_path.clone())),
+    if let Some(global_cfg) = &mut args.configs().lock().global_config {
-        )))
+        let value = UntaggedValue::Primitive(Primitive::FilePath(global_cfg.file_path.clone()))
+            .into_value(name);
+
+        Ok(OutputStream::one(value))
     } else {
-        Ok(vec![ReturnSuccess::value(UntaggedValue::Error(
+        let value = UntaggedValue::Error(crate::commands::config::err_no_global_cfg_present())
-            crate::commands::config::err_no_global_cfg_present(),
+            .into_value(name);
-        ))]
+
-        .into_iter()
+        Ok(OutputStream::one(value))
-        .to_action_stream())
     }
 }

crates/nu-command/src/commands/config/remove.rs

@@ -1,16 +1,11 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, UntaggedValue};
+use nu_protocol::{Signature, SyntaxShape, UntaggedValue, Value};
 use nu_source::Tagged;
 
 pub struct SubCommand;
 
-#[derive(Deserialize)]
-pub struct Arguments {
-    remove: Tagged<String>,
-}
-
 impl WholeStreamCommand for SubCommand {
     fn name(&self) -> &str {
         "config remove"
@@ -28,7 +23,7 @@ impl WholeStreamCommand for SubCommand {
         "Removes a value from the config"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         remove(args)
     }
 
@@ -41,9 +36,11 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-pub fn remove(args: CommandArgs) -> Result<ActionStream, ShellError> {
+pub fn remove(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let name = args.call_info.name_tag.clone();
     let ctx = EvaluationContext::from_args(&args);
-    let (Arguments { remove }, _) = args.process()?;
+    let args = args.evaluate_once()?;
+    let remove: Tagged<String> = args.req(0)?;
 
     let key = remove.to_string();
 
@@ -52,11 +49,10 @@ pub fn remove(args: CommandArgs) -> Result<ActionStream, ShellError> {
             global_cfg.vars.swap_remove(&key);
             global_cfg.write()?;
             ctx.reload_config(global_cfg)?;
-            Ok(vec![ReturnSuccess::value(
+
-                UntaggedValue::row(global_cfg.vars.clone()).into_value(remove.tag()),
+            let value: Value = UntaggedValue::row(global_cfg.vars.clone()).into_value(remove.tag);
-            )]
+
-            .into_iter()
+            Ok(OutputStream::one(value))
-            .to_action_stream())
         } else {
             Err(ShellError::labeled_error(
                 "Key does not exist in config",
@@ -65,11 +61,10 @@ pub fn remove(args: CommandArgs) -> Result<ActionStream, ShellError> {
             ))
         }
     } else {
-        Ok(vec![ReturnSuccess::value(UntaggedValue::Error(
+        let value = UntaggedValue::Error(crate::commands::config::err_no_global_cfg_present())
-            crate::commands::config::err_no_global_cfg_present(),
+            .into_value(name);
-        ))]
+
-        .into_iter()
+        Ok(OutputStream::one(value))
-        .to_action_stream())
     };
 
     result

crates/nu-command/src/commands/config/set.rs

@@ -1,16 +1,10 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ColumnPath, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_protocol::{Signature, SyntaxShape, UntaggedValue, Value};
 
 pub struct SubCommand;
 
-#[derive(Deserialize)]
-pub struct Arguments {
-    column_path: ColumnPath,
-    value: Value,
-}
-
 impl WholeStreamCommand for SubCommand {
     fn name(&self) -> &str {
         "config set"
@@ -26,7 +20,7 @@ impl WholeStreamCommand for SubCommand {
         "Sets a value in the config"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         set(args)
     }
 
@@ -56,16 +50,13 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-pub fn set(args: CommandArgs) -> Result<ActionStream, ShellError> {
+pub fn set(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let name = args.call_info.name_tag.clone();
     let ctx = EvaluationContext::from_args(&args);
-    let (
+    let args = args.evaluate_once()?;
-        Arguments {
+
-            column_path,
+    let column_path = args.req(0)?;
-            mut value,
+    let mut value: Value = args.req(1)?;
-        },
-        _,
-    ) = args.process()?;
 
     let result = if let Some(global_cfg) = &mut ctx.configs.lock().global_config {
         let configuration = UntaggedValue::row(global_cfg.vars.clone()).into_value(&name);
@@ -85,19 +76,17 @@ pub fn set(args: CommandArgs) -> Result<ActionStream, ShellError> {
                 global_cfg.write()?;
                 ctx.reload_config(global_cfg)?;
 
-                Ok(ActionStream::one(ReturnSuccess::value(
+                let value = UntaggedValue::row(global_cfg.vars.clone()).into_value(name);
-                    UntaggedValue::row(global_cfg.vars.clone()).into_value(name),
+                Ok(OutputStream::one(value))
-                )))
             }
-            Ok(_) => Ok(ActionStream::empty()),
+            Ok(_) => Ok(OutputStream::empty()),
             Err(reason) => Err(reason),
         }
     } else {
-        Ok(vec![ReturnSuccess::value(UntaggedValue::Error(
+        let value = UntaggedValue::Error(crate::commands::config::err_no_global_cfg_present())
-            crate::commands::config::err_no_global_cfg_present(),
+            .into_value(name);
-        ))]
+
-        .into_iter()
+        Ok(OutputStream::one(value))
-        .to_action_stream())
     };
 
     result

crates/nu-command/src/commands/config/set_into.rs

@@ -1,16 +1,11 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_protocol::{Signature, SyntaxShape, UntaggedValue, Value};
 use nu_source::Tagged;
 
 pub struct SubCommand;
 
-#[derive(Deserialize)]
-pub struct Arguments {
-    set_into: Tagged<String>,
-}
-
 impl WholeStreamCommand for SubCommand {
     fn name(&self) -> &str {
         "config set_into"
@@ -28,7 +23,7 @@ impl WholeStreamCommand for SubCommand {
         "Sets a value in the config"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         set_into(args)
     }
 
@@ -41,20 +36,22 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-pub fn set_into(args: CommandArgs) -> Result<ActionStream, ShellError> {
+pub fn set_into(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let name = args.call_info.name_tag.clone();
     let ctx = EvaluationContext::from_args(&args);
-    let (Arguments { set_into: v }, input) = args.process()?;
+    let args = args.evaluate_once()?;
 
-    let rows: Vec<Value> = input.collect();
+    let set_into: Tagged<String> = args.req(0)?;
-    let key = v.to_string();
+
+    let rows: Vec<Value> = args.input.collect();
+    let key = set_into.to_string();
 
     let result = if let Some(global_cfg) = &mut ctx.configs.lock().global_config {
         if rows.is_empty() {
             return Err(ShellError::labeled_error(
                 "No values given for set_into",
                 "needs value(s) from pipeline",
-                v.tag(),
+                set_into.tag(),
             ));
         } else if rows.len() == 1 {
             // A single value
@@ -71,15 +68,14 @@ pub fn set_into(args: CommandArgs) -> Result<ActionStream, ShellError> {
         global_cfg.write()?;
         ctx.reload_config(global_cfg)?;
 
-        Ok(ActionStream::one(ReturnSuccess::value(
+        let value = UntaggedValue::row(global_cfg.vars.clone()).into_value(name);
-            UntaggedValue::row(global_cfg.vars.clone()).into_value(name),
+
-        )))
+        Ok(OutputStream::one(value))
     } else {
-        Ok(vec![ReturnSuccess::value(UntaggedValue::Error(
+        let value = UntaggedValue::Error(crate::commands::config::err_no_global_cfg_present())
-            crate::commands::config::err_no_global_cfg_present(),
+            .into_value(name);
-        ))]
+
-        .into_iter()
+        Ok(OutputStream::one(value))
-        .to_action_stream())
     };
 
     result

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

@@ -26,7 +26,7 @@ impl WholeStreamCommand for Cpy {
     }
 
     fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
-        let shell_manager = args.shell_manager.clone();
+        let shell_manager = args.shell_manager();
         let name = args.call_info.name_tag.clone();
         let (args, _) = args.process()?;
         shell_manager.cp(args, name)

crates/nu-command/src/commands/dataframe/aggregate.rs

@@ -0,0 +1,202 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{NuDataFrame, PolarsData},
+    Signature, SyntaxShape, UntaggedValue, Value,
+};
+use nu_source::Tagged;
+use polars::frame::groupby::GroupBy;
+
+use super::utils::convert_columns;
+
+enum Operation {
+    Mean,
+    Sum,
+    Min,
+    Max,
+    First,
+    Last,
+    Nunique,
+    Quantile(f64),
+    Median,
+    Var,
+    Std,
+    Count,
+}
+
+impl Operation {
+    fn from_tagged(
+        name: &Tagged<String>,
+        quantile: Option<Tagged<f64>>,
+    ) -> Result<Operation, ShellError> {
+        match name.item.as_ref() {
+            "mean" => Ok(Operation::Mean),
+            "sum" => Ok(Operation::Sum),
+            "min" => Ok(Operation::Min),
+            "max" => Ok(Operation::Max),
+            "first" => Ok(Operation::First),
+            "last" => Ok(Operation::Last),
+            "nunique" => Ok(Operation::Nunique),
+            "quantile" => {
+                match quantile {
+                    None => Err(ShellError::labeled_error(
+                        "Quantile value not fount",
+                        "Quantile operation requires quantile value",
+                        &name.tag,
+                    )),
+                Some(value ) => {
+                    if (value.item < 0.0) | (value.item > 1.0) {
+                        Err(ShellError::labeled_error(
+                            "Inappropriate quantile",
+                            "Quantile value should be between 0.0 and 1.0",
+                            &value.tag,
+                        ))
+                    } else {
+                        Ok(Operation::Quantile(value.item))
+                    }
+                }
+                }
+            }
+            "median" => Ok(Operation::Median),
+            "var" => Ok(Operation::Var),
+            "std" => Ok(Operation::Std),
+            "count" => Ok(Operation::Count),
+            _ => Err(ShellError::labeled_error_with_secondary(
+                "Operation not fount",
+                "Operation does not exist",
+                &name.tag,
+                "Perhaps you want: mean, sum, min, max, first, last, nunique, quantile, median, count",
+                &name.tag,
+            )),
+        }
+    }
+}
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "pls aggregate"
+    }
+
+    fn usage(&self) -> &str {
+        "Performs an aggregation operation on a groupby object"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pls aggregate")
+            .required("operation", SyntaxShape::String, "aggregate operation")
+            .optional(
+                "selection",
+                SyntaxShape::Table,
+                "columns to perform aggregation",
+            )
+            .named(
+                "quantile",
+                SyntaxShape::Number,
+                "quantile value for quantile operation",
+                Some('q'),
+            )
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        aggregate(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Aggregate sum by grouping by column a and summing on col b",
+            example:
+                "echo [[a b]; [one 1] [one 2]] | pls convert | pls groupby [a] | pls aggregate sum",
+            result: None,
+        }]
+    }
+}
+
+fn aggregate(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let mut args = args.evaluate_once()?;
+
+    let quantile: Option<Tagged<f64>> = args.get_flag("quantile")?;
+    let operation: Tagged<String> = args.req(0)?;
+    let op = Operation::from_tagged(&operation, quantile)?;
+
+    // Extracting the selection columns of the columns to perform the aggregation
+    let agg_cols: Option<Vec<Value>> = args.opt(1)?;
+    let (selection, agg_span) = match agg_cols {
+        Some(cols) => {
+            let (agg_string, agg_span) = convert_columns(&cols, &tag)?;
+            (Some(agg_string), agg_span)
+        }
+        None => (None, Span::unknown()),
+    };
+
+    // The operation is only done in one dataframe. Only one input is
+    // expected from the InputStream
+    match args.input.next() {
+        None => Err(ShellError::labeled_error(
+            "No input received",
+            "missing dataframe input from stream",
+            &tag,
+        )),
+        Some(value) => {
+            if let UntaggedValue::DataFrame(PolarsData::GroupBy(nu_groupby)) = value.value {
+                let groupby = nu_groupby.to_groupby()?;
+
+                let groupby = match &selection {
+                    Some(cols) => groupby.select(cols),
+                    None => groupby,
+                };
+
+                let res = perform_aggregation(groupby, op, &operation.tag, &agg_span)?;
+
+                let final_df = Value {
+                    tag,
+                    value: UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame::new(
+                        res,
+                    ))),
+                };
+
+                Ok(OutputStream::one(final_df))
+            } else {
+                Err(ShellError::labeled_error(
+                    "No groupby in stream",
+                    "no groupby found in input stream",
+                    &tag,
+                ))
+            }
+        }
+    }
+}
+
+fn perform_aggregation(
+    groupby: GroupBy,
+    operation: Operation,
+    operation_tag: &Tag,
+    agg_span: &Span,
+) -> Result<polars::prelude::DataFrame, ShellError> {
+    match operation {
+        Operation::Mean => groupby.mean(),
+        Operation::Sum => groupby.sum(),
+        Operation::Min => groupby.min(),
+        Operation::Max => groupby.max(),
+        Operation::First => groupby.first(),
+        Operation::Last => groupby.last(),
+        Operation::Nunique => groupby.n_unique(),
+        Operation::Quantile(quantile) => groupby.quantile(quantile),
+        Operation::Median => groupby.median(),
+        Operation::Var => groupby.var(),
+        Operation::Std => groupby.std(),
+        Operation::Count => groupby.count(),
+    }
+    .map_err(|e| {
+        let span = if e.to_string().contains("Not found") {
+            agg_span
+        } else {
+            &operation_tag.span
+        };
+
+        ShellError::labeled_error("Aggregation error", format!("{}", e), span)
+    })
+}

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

@@ -0,0 +1,26 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{Signature, UntaggedValue};
+
+pub struct Command;
+
+impl WholeStreamCommand for Command {
+    fn name(&self) -> &str {
+        "pls"
+    }
+
+    fn usage(&self) -> &str {
+        "Commands to work with polars dataframes"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pls")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        Ok(OutputStream::one(
+            UntaggedValue::string(get_full_help(&Command, args.scope())).into_value(Tag::unknown()),
+        ))
+    }
+}

crates/nu-command/src/commands/dataframe/convert.rs

@@ -0,0 +1,43 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{NuDataFrame, PolarsData},
+    Signature, UntaggedValue,
+};
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "pls convert"
+    }
+
+    fn usage(&self) -> &str {
+        "Converts a pipelined Table or List into a polars dataframe"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pls convert")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        let tag = args.call_info.name_tag.clone();
+        let args = args.evaluate_once()?;
+
+        let df = NuDataFrame::try_from_iter(args.input, &tag)?;
+        let init = InputStream::one(
+            UntaggedValue::DataFrame(PolarsData::EagerDataFrame(df)).into_value(&tag),
+        );
+
+        Ok(init.to_output_stream())
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Takes an input stream and converts it to a polars dataframe",
+            example: "echo [[a b];[1 2] [3 4]] | pls convert",
+            result: None,
+        }]
+    }
+}

crates/nu-command/src/commands/dataframe/drop.rs

@@ -0,0 +1,97 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{NuDataFrame, PolarsData},
+    Signature, SyntaxShape, UntaggedValue, Value,
+};
+
+use super::utils::convert_columns;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "pls drop"
+    }
+
+    fn usage(&self) -> &str {
+        "Creates a new dataframe by dropping the selected columns"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pls drop").required(
+            "columns",
+            SyntaxShape::Table,
+            "column names to be dropped",
+        )
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        drop(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "drop column a",
+            example: "echo [[a b]; [1 2] [3 4]] | pls convert | pls drop [a]",
+            result: None,
+        }]
+    }
+}
+
+fn drop(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let mut args = args.evaluate_once()?;
+
+    let columns: Vec<Value> = args.req(0)?;
+
+    let (col_string, col_span) = convert_columns(&columns, &tag)?;
+
+    match args.input.next() {
+        None => Err(ShellError::labeled_error(
+            "No input received",
+            "missing dataframe input from stream",
+            &tag,
+        )),
+        Some(value) => {
+            if let UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame {
+                dataframe: Some(ref df),
+                ..
+            })) = value.value
+            {
+                let new_df = match col_string.iter().next() {
+                    Some(col) => df.drop(col).map_err(|e| {
+                        ShellError::labeled_error("Join error", format!("{}", e), &col_span)
+                    }),
+                    None => Err(ShellError::labeled_error(
+                        "Empty names list",
+                        "No column names where found",
+                        &col_span,
+                    )),
+                }?;
+
+                let res = col_string.iter().skip(1).try_fold(new_df, |new_df, col| {
+                    new_df.drop(col).map_err(|e| {
+                        ShellError::labeled_error("Drop error", format!("{}", e), &col_span)
+                    })
+                })?;
+
+                let value = Value {
+                    value: UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame::new(
+                        res,
+                    ))),
+                    tag: tag.clone(),
+                };
+
+                Ok(OutputStream::one(value))
+            } else {
+                Err(ShellError::labeled_error(
+                    "No dataframe in stream",
+                    "no dataframe found in input stream",
+                    &tag,
+                ))
+            }
+        }
+    }
+}

crates/nu-command/src/commands/dataframe/dtypes.rs

@@ -0,0 +1,81 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{NuDataFrame, PolarsData},
+    Signature, TaggedDictBuilder, UntaggedValue,
+};
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "pls dtypes"
+    }
+
+    fn usage(&self) -> &str {
+        "Show dataframe data types"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pls dtypes")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        dtypes(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "drop column a",
+            example: "echo [[a b]; [1 2] [3 4]] | pls convert | pls dtypes",
+            result: None,
+        }]
+    }
+}
+
+fn dtypes(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let mut args = args.evaluate_once()?;
+
+    match args.input.next() {
+        None => Err(ShellError::labeled_error(
+            "No input received",
+            "missing dataframe input from stream",
+            &tag,
+        )),
+        Some(value) => {
+            if let UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame {
+                dataframe: Some(df),
+                ..
+            })) = value.value
+            {
+                let col_names = df
+                    .get_column_names()
+                    .iter()
+                    .map(|v| v.to_string())
+                    .collect::<Vec<String>>();
+
+                let values =
+                    df.dtypes()
+                        .into_iter()
+                        .zip(col_names.into_iter())
+                        .map(move |(dtype, name)| {
+                            let mut data = TaggedDictBuilder::new(tag.clone());
+                            data.insert_value("column", name.as_ref());
+                            data.insert_value("dtype", format!("{}", dtype));
+
+                            data.into_value()
+                        });
+
+                Ok(OutputStream::from_stream(values))
+            } else {
+                Err(ShellError::labeled_error(
+                    "No dataframe in stream",
+                    "no dataframe found in input stream",
+                    &tag,
+                ))
+            }
+        }
+    }
+}

crates/nu-command/src/commands/dataframe/groupby.rs

@@ -0,0 +1,94 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{NuDataFrame, NuGroupBy, PolarsData},
+    Signature, SyntaxShape, UntaggedValue, Value,
+};
+
+use super::utils::convert_columns;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "pls groupby"
+    }
+
+    fn usage(&self) -> &str {
+        "Creates a groupby object that can be used for other aggregations"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pls groupby").required(
+            "by columns",
+            SyntaxShape::Table,
+            "groupby columns",
+        )
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        groupby(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Grouping by column a",
+            example: "echo [[a b]; [one 1] [one 2]] | pls convert | pls groupby [a]",
+            result: None,
+        }]
+    }
+}
+
+fn groupby(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let mut args = args.evaluate_once()?;
+
+    // Extracting the names of the columns to perform the groupby
+    let by_columns: Vec<Value> = args.req(0)?;
+    let (columns_string, col_span) = convert_columns(&by_columns, &tag)?;
+
+    // The operation is only done in one dataframe. Only one input is
+    // expected from the InputStream
+    match args.input.next() {
+        None => Err(ShellError::labeled_error(
+            "No input received",
+            "missing dataframe input from stream",
+            &tag,
+        )),
+        Some(value) => {
+            if let UntaggedValue::DataFrame(PolarsData::EagerDataFrame(nu_df)) = value.value {
+                let df = match nu_df.dataframe {
+                    Some(df) => df,
+                    None => unreachable!("No dataframe in nu_dataframe"),
+                };
+
+                // This is the expensive part of the groupby; to create the
+                // groups that will be used for grouping the data in the
+                // dataframe. Once it has been done these values can be stored
+                // in the NuGroupBy
+                let groupby = df.groupby(&columns_string).map_err(|e| {
+                    ShellError::labeled_error("Groupby error", format!("{}", e), col_span)
+                })?;
+
+                let groups = groupby.get_groups().to_vec();
+                let groupby = Value {
+                    tag: value.tag,
+                    value: UntaggedValue::DataFrame(PolarsData::GroupBy(NuGroupBy::new(
+                        NuDataFrame::new_with_name(df, nu_df.name),
+                        columns_string,
+                        groups,
+                    ))),
+                };
+
+                Ok(OutputStream::one(groupby))
+            } else {
+                Err(ShellError::labeled_error(
+                    "No dataframe in stream",
+                    "no dataframe found in input stream",
+                    &tag,
+                ))
+            }
+        }
+    }
+}

crates/nu-command/src/commands/dataframe/join.rs

@@ -0,0 +1,205 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{NuDataFrame, PolarsData},
+    Signature, SyntaxShape, UntaggedValue, Value,
+};
+
+use super::utils::convert_columns;
+
+use polars::prelude::JoinType;
+
+use nu_source::Tagged;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "pls join"
+    }
+
+    fn usage(&self) -> &str {
+        "Joins a dataframe using columns as reference"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pls join")
+            .required("dataframe", SyntaxShape::Any, "right dataframe to join")
+            .required(
+                "l_columns",
+                SyntaxShape::Table,
+                "left column names to perform join",
+            )
+            .required(
+                "r_columns",
+                SyntaxShape::Table,
+                "right column names to perform join",
+            )
+            .named(
+                "type",
+                SyntaxShape::String,
+                "type of join. Inner by default",
+                Some('t'),
+            )
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        join(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "inner join dataframe",
+                example: "echo [[a b]; [1 2] [3 4]] | pls convert | pls join $right [a] [a]",
+                result: None,
+            },
+            Example {
+                description: "right join dataframe",
+                example:
+                    "echo [[a b]; [1 2] [3 4] [5 6]] | pls convert | pls join $right [b] [b] -t right",
+                result: None,
+            },
+        ]
+    }
+}
+
+fn join(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let mut args = args.evaluate_once()?;
+
+    let r_df: Value = args.req(0)?;
+    let l_col: Vec<Value> = args.req(1)?;
+    let r_col: Vec<Value> = args.req(2)?;
+    let join_type_op: Option<Tagged<String>> = args.get_flag("type")?;
+
+    let join_type = match join_type_op {
+        None => JoinType::Inner,
+        Some(val) => match val.item.as_ref() {
+            "inner" => JoinType::Inner,
+            "outer" => JoinType::Outer,
+            "left" => JoinType::Left,
+            _ => {
+                return Err(ShellError::labeled_error_with_secondary(
+                    "Incorrect join type",
+                    "Invalid join type",
+                    &val.tag,
+                    "Perhaps you mean: inner, outer or left",
+                    &val.tag,
+                ))
+            }
+        },
+    };
+
+    let (l_col_string, l_col_span) = convert_columns(&l_col, &tag)?;
+    let (r_col_string, r_col_span) = convert_columns(&r_col, &tag)?;
+
+    match args.input.next() {
+        None => Err(ShellError::labeled_error(
+            "No input received",
+            "missing dataframe input from stream",
+            &tag,
+        )),
+        Some(value) => {
+            if let UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame {
+                dataframe: Some(ref df),
+                ..
+            })) = value.value
+            {
+                let res = match r_df.value {
+                    UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame {
+                        dataframe: Some(r_df),
+                        ..
+                    })) => {
+                        // Checking the column types before performing the join
+                        check_column_datatypes(
+                            df,
+                            &l_col_string,
+                            &l_col_span,
+                            &r_col_string,
+                            &r_col_span,
+                        )?;
+
+                        df.join(&r_df, &l_col_string, &r_col_string, join_type)
+                            .map_err(|e| {
+                                ShellError::labeled_error(
+                                    "Join error",
+                                    format!("{}", e),
+                                    &l_col_span,
+                                )
+                            })
+                    }
+                    _ => Err(ShellError::labeled_error(
+                        "Not a dataframe",
+                        "not a dataframe type value",
+                        &r_df.tag,
+                    )),
+                }?;
+
+                let value = Value {
+                    value: UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame::new(
+                        res,
+                    ))),
+                    tag: tag.clone(),
+                };
+
+                Ok(OutputStream::one(value))
+            } else {
+                Err(ShellError::labeled_error(
+                    "No dataframe in stream",
+                    "no dataframe found in input stream",
+                    &tag,
+                ))
+            }
+        }
+    }
+}
+
+fn check_column_datatypes<T: AsRef<str>>(
+    df: &polars::prelude::DataFrame,
+    l_cols: &[T],
+    l_col_span: &Span,
+    r_cols: &[T],
+    r_col_span: &Span,
+) -> Result<(), ShellError> {
+    if l_cols.len() != r_cols.len() {
+        return Err(ShellError::labeled_error_with_secondary(
+            "Mismatched number of column names",
+            format!(
+                "found {} left names vs {} right names",
+                l_cols.len(),
+                r_cols.len()
+            ),
+            l_col_span,
+            "perhaps you need to change the number of columns to join",
+            r_col_span,
+        ));
+    }
+
+    for (l, r) in l_cols.iter().zip(r_cols.iter()) {
+        let l_series = df
+            .column(l.as_ref())
+            .map_err(|e| ShellError::labeled_error("Join error", format!("{}", e), l_col_span))?;
+
+        let r_series = df
+            .column(r.as_ref())
+            .map_err(|e| ShellError::labeled_error("Join error", format!("{}", e), r_col_span))?;
+
+        if l_series.dtype() != r_series.dtype() {
+            return Err(ShellError::labeled_error_with_secondary(
+                "Mismatched datatypes",
+                format!(
+                    "left column type '{}' doesn't match '{}' right column match",
+                    l_series.dtype(),
+                    r_series.dtype()
+                ),
+                l_col_span,
+                "perhaps you need to select other column to match",
+                r_col_span,
+            ));
+        }
+    }
+
+    Ok(())
+}

crates/nu-command/src/commands/dataframe/list.rs

@@ -0,0 +1,64 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{NuDataFrame, PolarsData},
+    Signature, TaggedDictBuilder, UntaggedValue,
+};
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "pls list"
+    }
+
+    fn usage(&self) -> &str {
+        "Lists stored dataframes"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pls list")
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        let args = args.evaluate_once()?;
+
+        let values = args
+            .context
+            .scope
+            .get_vars()
+            .into_iter()
+            .filter_map(|(name, value)| {
+                if let UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame {
+                    dataframe: Some(df),
+                    name: file_name,
+                })) = &value.value
+                {
+                    let mut data = TaggedDictBuilder::new(value.tag.clone());
+
+                    let rows = df.height();
+                    let cols = df.width();
+
+                    data.insert_value("name", name.as_ref());
+                    data.insert_value("file", file_name.as_ref());
+                    data.insert_value("rows", format!("{}", rows));
+                    data.insert_value("columns", format!("{}", cols));
+
+                    Some(data.into_value())
+                } else {
+                    None
+                }
+            });
+
+        Ok(OutputStream::from_stream(values))
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Lists loaded dataframes in current scope",
+            example: "pls list",
+            result: None,
+        }]
+    }
+}

crates/nu-command/src/commands/dataframe/load.rs

@@ -0,0 +1,221 @@
+use std::path::PathBuf;
+
+use crate::prelude::*;
+use nu_engine::{EvaluatedCommandArgs, WholeStreamCommand};
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{NuDataFrame, PolarsData},
+    Primitive, Signature, SyntaxShape, UntaggedValue, Value,
+};
+
+use nu_source::Tagged;
+use polars::prelude::{CsvReader, JsonReader, ParquetReader, SerReader};
+use std::fs::File;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "pls load"
+    }
+
+    fn usage(&self) -> &str {
+        "Loads dataframe form csv file"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pls load")
+            .required(
+                "file",
+                SyntaxShape::FilePath,
+                "the file path to load values from",
+            )
+            .named(
+                "delimiter",
+                SyntaxShape::String,
+                "file delimiter character. CSV file",
+                Some('d'),
+            )
+            .switch(
+                "no_header",
+                "Indicates if file doesn't have header. CSV file",
+                None,
+            )
+            .named(
+                "infer_schema",
+                SyntaxShape::Number,
+                "Set number of row to infer the schema of the file. CSV file",
+                None,
+            )
+            .named(
+                "skip_rows",
+                SyntaxShape::Number,
+                "Number of rows to skip from file. CSV file",
+                None,
+            )
+            .named(
+                "columns",
+                SyntaxShape::Table,
+                "Columns to be selected from csv file. CSV file",
+                None,
+            )
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        create_from_file(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Takes a file name and creates a dataframe",
+            example: "pls load test.csv",
+            result: None,
+        }]
+    }
+}
+
+fn create_from_file(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let args = args.evaluate_once()?;
+    let file: Tagged<PathBuf> = args.req(0)?;
+
+    let df = match file.item().extension() {
+        Some(e) => match e.to_str() {
+            Some("csv") => from_csv(args),
+            Some("parquet") => from_parquet(args),
+            Some("json") => from_json(args),
+            _ => Err(ShellError::labeled_error(
+                "Error with file",
+                "Not a csv, parquet or json file",
+                &file.tag,
+            )),
+        },
+        None => Err(ShellError::labeled_error(
+            "Error with file",
+            "File without extension",
+            &file.tag,
+        )),
+    }?;
+
+    let file_name = match file.item.into_os_string().into_string() {
+        Ok(name) => name,
+        Err(e) => {
+            return Err(ShellError::labeled_error(
+                "Error with file name",
+                format!("{:?}", e),
+                &file.tag,
+            ))
+        }
+    };
+
+    let init = InputStream::one(
+        UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame::new_with_name(
+            df, file_name,
+        )))
+        .into_value(&tag),
+    );
+
+    Ok(init.to_output_stream())
+}
+
+fn from_parquet(args: EvaluatedCommandArgs) -> Result<polars::prelude::DataFrame, ShellError> {
+    let file: Tagged<PathBuf> = args.req(0)?;
+
+    let r = File::open(&file.item)
+        .map_err(|e| ShellError::labeled_error("Error with file", format!("{:?}", e), &file.tag))?;
+
+    let reader = ParquetReader::new(r);
+
+    reader
+        .finish()
+        .map_err(|e| ShellError::labeled_error("Error with file", format!("{:?}", e), &file.tag))
+}
+
+fn from_json(args: EvaluatedCommandArgs) -> Result<polars::prelude::DataFrame, ShellError> {
+    let file: Tagged<PathBuf> = args.req(0)?;
+
+    let r = File::open(&file.item)
+        .map_err(|e| ShellError::labeled_error("Error with file", format!("{:?}", e), &file.tag))?;
+
+    let reader = JsonReader::new(r);
+
+    reader
+        .finish()
+        .map_err(|e| ShellError::labeled_error("Error with file", format!("{:?}", e), &file.tag))
+}
+
+fn from_csv(args: EvaluatedCommandArgs) -> Result<polars::prelude::DataFrame, ShellError> {
+    let file: Tagged<PathBuf> = args.req(0)?;
+    let delimiter: Option<Tagged<String>> = args.get_flag("delimiter")?;
+    let no_header: bool = args.has_flag("no_header");
+    let infer_schema: Option<Tagged<usize>> = args.get_flag("infer_schema")?;
+    let skip_rows: Option<Tagged<usize>> = args.get_flag("skip_rows")?;
+    let columns: Option<Vec<Value>> = args.get_flag("columns")?;
+
+    let csv_reader = CsvReader::from_path(&file.item).map_err(|e| {
+        ShellError::labeled_error("Unable to parse file", format!("{}", e), &file.tag)
+    })?;
+
+    let csv_reader = match delimiter {
+        None => csv_reader,
+        Some(d) => {
+            if d.item.len() != 1 {
+                return Err(ShellError::labeled_error(
+                    "Incorrect delimiter",
+                    "Delimiter has to be one char",
+                    &d.tag,
+                ));
+            } else {
+                let delimiter = match d.item.chars().nth(0) {
+                    Some(d) => d as u8,
+                    None => unreachable!(),
+                };
+                csv_reader.with_delimiter(delimiter)
+            }
+        }
+    };
+
+    let csv_reader = if no_header {
+        csv_reader.has_header(false)
+    } else {
+        csv_reader.has_header(true)
+    };
+
+    let csv_reader = match infer_schema {
+        None => csv_reader.infer_schema(None),
+        Some(r) => csv_reader.infer_schema(Some(r.item)),
+    };
+
+    let csv_reader = match skip_rows {
+        None => csv_reader,
+        Some(r) => csv_reader.with_skip_rows(r.item),
+    };
+
+    let csv_reader = match columns {
+        None => csv_reader,
+        Some(c) => {
+            let columns = c
+                .into_iter()
+                .map(|value| match value.value {
+                    UntaggedValue::Primitive(Primitive::String(s)) => Ok(s),
+                    _ => Err(ShellError::labeled_error(
+                        "Incorrect type for column",
+                        "Only string as columns",
+                        &value.tag,
+                    )),
+                })
+                .collect::<Result<Vec<String>, ShellError>>();
+
+            csv_reader.with_columns(Some(columns?))
+        }
+    };
+
+    match csv_reader.finish() {
+        Ok(csv_reader) => Ok(csv_reader),
+        Err(e) => Err(ShellError::labeled_error(
+            "Error while parsing dataframe",
+            format!("{}", e),
+            &file.tag,
+        )),
+    }
+}

crates/nu-command/src/commands/dataframe/mod.rs

@@ -0,0 +1,26 @@
+pub mod aggregate;
+pub mod command;
+pub mod convert;
+pub mod drop;
+pub mod dtypes;
+pub mod groupby;
+pub mod join;
+pub mod list;
+pub mod load;
+pub mod sample;
+pub mod select;
+pub mod show;
+pub(crate) mod utils;
+
+pub use aggregate::DataFrame as DataFrameAggregate;
+pub use command::Command as DataFrame;
+pub use convert::DataFrame as DataFrameConvert;
+pub use drop::DataFrame as DataFrameDrop;
+pub use dtypes::DataFrame as DataFrameDTypes;
+pub use groupby::DataFrame as DataFrameGroupBy;
+pub use join::DataFrame as DataFrameJoin;
+pub use list::DataFrame as DataFrameList;
+pub use load::DataFrame as DataFrameLoad;
+pub use sample::DataFrame as DataFrameSample;
+pub use select::DataFrame as DataFrameSelect;
+pub use show::DataFrame as DataFrameShow;

crates/nu-command/src/commands/dataframe/sample.rs

@@ -0,0 +1,117 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{NuDataFrame, PolarsData},
+    Signature, SyntaxShape, UntaggedValue, Value,
+};
+
+use nu_source::Tagged;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "pls sample"
+    }
+
+    fn usage(&self) -> &str {
+        "Create sample dataframe"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pls load")
+            .named(
+                "n_rows",
+                SyntaxShape::Number,
+                "number of rows to be taken from dataframe",
+                Some('n'),
+            )
+            .named(
+                "fraction",
+                SyntaxShape::Number,
+                "fraction of dataframe to be taken",
+                Some('f'),
+            )
+            .switch("replace", "sample with replace", Some('e'))
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        sample(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Sample rows from dataframe",
+                example: "echo [[a b]; [1 2] [3 4]] | pls load | pls sample -r 1",
+                result: None,
+            },
+            Example {
+                description: "Shows sample row using fraction and replace",
+                example: "echo [[a b]; [1 2] [3 4] [5 6]] | pls load | pls sample -f 0.5 -e",
+                result: None,
+            },
+        ]
+    }
+}
+
+fn sample(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let mut args = args.evaluate_once()?;
+
+    let rows: Option<Tagged<usize>> = args.get_flag("n_rows")?;
+    let fraction: Option<Tagged<f64>> = args.get_flag("fraction")?;
+    let replace: bool = args.has_flag("replace");
+
+    match args.input.next() {
+        None => Err(ShellError::labeled_error(
+            "No input received",
+            "missing dataframe input from stream",
+            &tag,
+        )),
+        Some(value) => {
+            if let UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame {
+                dataframe: Some(ref df),
+                ..
+            })) = value.value
+            {
+                let res = match (rows, fraction) {
+                    (Some(rows), None) => df.sample_n(rows.item, replace).map_err(|e| {
+                        ShellError::labeled_error("Polars error", format!("{}", e), &rows.tag)
+                    }),
+                    (None, Some(frac)) => df.sample_frac(frac.item, replace).map_err(|e| {
+                        ShellError::labeled_error("Polars error", format!("{}", e), &frac.tag)
+                    }),
+                    (Some(_), Some(_)) => Err(ShellError::labeled_error(
+                        "Incompatible flags",
+                        "Only one selection criterion allowed",
+                        &tag,
+                    )),
+                    (None, None) => Err(ShellError::labeled_error_with_secondary(
+                        "No selection",
+                        "No selection criterion was found",
+                        &tag,
+                        "Perhaps you want to use the flag -n or -f",
+                        &tag,
+                    )),
+                }?;
+
+                let value = Value {
+                    value: UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame::new(
+                        res,
+                    ))),
+                    tag: tag.clone(),
+                };
+
+                Ok(OutputStream::one(value))
+            } else {
+                Err(ShellError::labeled_error(
+                    "No dataframe in stream",
+                    "no dataframe found in input stream",
+                    &tag,
+                ))
+            }
+        }
+    }
+}

crates/nu-command/src/commands/dataframe/select.rs

@@ -0,0 +1,84 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{
+    dataframe::{NuDataFrame, PolarsData},
+    Signature, SyntaxShape, UntaggedValue, Value,
+};
+
+use super::utils::convert_columns;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "pls select"
+    }
+
+    fn usage(&self) -> &str {
+        "Creates a new dataframe with the selected columns"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pls select").required(
+            "columns",
+            SyntaxShape::Table,
+            "selected column names",
+        )
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        select(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Create new dataframe with column a",
+            example: "echo [[a b]; [1 2] [3 4]] | pls convert | pls select [a]",
+            result: None,
+        }]
+    }
+}
+
+fn select(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let mut args = args.evaluate_once()?;
+
+    let columns: Vec<Value> = args.req(0)?;
+
+    let (col_string, col_span) = convert_columns(&columns, &tag)?;
+
+    match args.input.next() {
+        None => Err(ShellError::labeled_error(
+            "No input received",
+            "missing dataframe input from stream",
+            &tag,
+        )),
+        Some(value) => {
+            if let UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame {
+                dataframe: Some(ref df),
+                ..
+            })) = value.value
+            {
+                let res = df.select(&col_string).map_err(|e| {
+                    ShellError::labeled_error("Drop error", format!("{}", e), &col_span)
+                })?;
+
+                let value = Value {
+                    value: UntaggedValue::DataFrame(PolarsData::EagerDataFrame(NuDataFrame::new(
+                        res,
+                    ))),
+                    tag: tag.clone(),
+                };
+
+                Ok(OutputStream::one(value))
+            } else {
+                Err(ShellError::labeled_error(
+                    "No dataframe in stream",
+                    "no dataframe found in input stream",
+                    &tag,
+                ))
+            }
+        }
+    }
+}

crates/nu-command/src/commands/dataframe/show.rs

@@ -0,0 +1,78 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{dataframe::PolarsData, Signature, SyntaxShape, UntaggedValue};
+
+use nu_source::Tagged;
+
+pub struct DataFrame;
+
+impl WholeStreamCommand for DataFrame {
+    fn name(&self) -> &str {
+        "pls show"
+    }
+
+    fn usage(&self) -> &str {
+        "Show dataframe"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("pls show")
+            .named(
+                "n_rows",
+                SyntaxShape::Number,
+                "number of rows to be shown",
+                Some('n'),
+            )
+            .switch("tail", "shows tail rows", Some('t'))
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        show(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Shows head rows from dataframe",
+                example: "echo [[a b]; [1 2] [3 4]] | pls convert | pls show",
+                result: None,
+            },
+            Example {
+                description: "Shows tail rows from dataframe",
+                example: "echo [[a b]; [1 2] [3 4] [5 6]] | pls convert | pls show -t -n 1",
+                result: None,
+            },
+        ]
+    }
+}
+
+fn show(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let tag = args.call_info.name_tag.clone();
+    let mut args = args.evaluate_once()?;
+
+    let rows: Option<Tagged<usize>> = args.get_flag("rows")?;
+    let tail: bool = args.has_flag("tail");
+
+    match args.input.next() {
+        None => Err(ShellError::labeled_error(
+            "No input received",
+            "missing dataframe input from stream",
+            &tag,
+        )),
+        Some(value) => {
+            if let UntaggedValue::DataFrame(PolarsData::EagerDataFrame(df)) = value.value {
+                let rows = rows.map(|v| v.item);
+                let values = if tail { df.tail(rows)? } else { df.head(rows)? };
+
+                Ok(OutputStream::from_stream(values.into_iter()))
+            } else {
+                Err(ShellError::labeled_error(
+                    "No dataframe in stream",
+                    "no dataframe found in input stream",
+                    &tag,
+                ))
+            }
+        }
+    }
+}

crates/nu-command/src/commands/dataframe/utils.rs

@@ -0,0 +1,42 @@
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, UntaggedValue, Value};
+
+// Converts a Vec<Value> to a Vec<String> with a Span marking the whole
+// location of the columns for error referencing
+pub(crate) fn convert_columns<'columns>(
+    columns: &'columns [Value],
+    tag: &Tag,
+) -> Result<(Vec<String>, Span), ShellError> {
+    let mut col_span = match columns
+        .iter()
+        .nth(0)
+        .map(|v| Span::new(v.tag.span.start(), v.tag.span.end()))
+    {
+        Some(span) => span,
+        None => {
+            return Err(ShellError::labeled_error(
+                "Empty column list",
+                "Empty list found for command",
+                tag,
+            ))
+        }
+    };
+
+    let res = columns
+        .iter()
+        .map(|value| match &value.value {
+            UntaggedValue::Primitive(Primitive::String(s)) => {
+                col_span = col_span.until(value.tag.span);
+                Ok(s.clone())
+            }
+            _ => Err(ShellError::labeled_error(
+                "Incorrect column format",
+                "Only string as column name",
+                &value.tag,
+            )),
+        })
+        .collect::<Result<Vec<String>, _>>()?;
+
+    Ok((res, col_span))
+}

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

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, Signature, UntaggedValue};
+use nu_protocol::{Signature, UntaggedValue};
 
 pub struct Command;
 
@@ -18,10 +18,10 @@ impl WholeStreamCommand for Command {
         "Apply date function."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
-        Ok(ActionStream::one(ReturnSuccess::value(
+        Ok(OutputStream::one(
-            UntaggedValue::string(get_full_help(&Command, &args.scope)).into_value(Tag::unknown()),
+            UntaggedValue::string(get_full_help(&Command, args.scope())).into_value(Tag::unknown()),
-        )))
+        ))
     }
 }
 

crates/nu-command/src/commands/date/format.rs

@@ -1,20 +1,12 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{
+use nu_protocol::{Dictionary, Primitive, Signature, SyntaxShape, UntaggedValue, Value};
-    Dictionary, Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
-};
 use nu_source::Tagged;
 use std::fmt::{self, write};
 
 pub struct Date;
 
-#[derive(Deserialize)]
-pub struct FormatArgs {
-    format: Tagged<String>,
-    table: bool,
-}
-
 impl WholeStreamCommand for Date {
     fn name(&self) -> &str {
         "date format"
@@ -30,7 +22,7 @@ impl WholeStreamCommand for Date {
         "Format a given date using the given format string."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         format(args)
     }
 
@@ -50,9 +42,18 @@ impl WholeStreamCommand for Date {
     }
 }
 
-pub fn format(args: CommandArgs) -> Result<ActionStream, ShellError> {
+pub fn format(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let tag = args.call_info.name_tag.clone();
-    let (FormatArgs { format, table }, input) = args.process()?;
+    let args = args.evaluate_once()?;
+
+    let format: Tagged<String> = args.req(0)?;
+    let table: Option<bool> = args.get_flag("table")?;
+
+    let input = if args.input.is_empty() {
+        InputStream::one(crate::commands::date::now::date_now(&tag))
+    } else {
+        args.input
+    };
 
     Ok(input
         .map(move |value| match value {
@@ -70,7 +71,7 @@ pub fn format(args: CommandArgs) -> Result<ActionStream, ShellError> {
                         &format.tag,
                     ))
                 } else {
-                    let value = if table {
+                    let value = if table.is_some() {
                         let mut indexmap = IndexMap::new();
                         indexmap.insert(
                             "formatted".to_string(),
@@ -82,7 +83,7 @@ pub fn format(args: CommandArgs) -> Result<ActionStream, ShellError> {
                         UntaggedValue::string(&output).into_value(&tag)
                     };
 
-                    ReturnSuccess::value(value)
+                    Ok(value)
                 }
             }
             _ => Err(ShellError::labeled_error(
@@ -91,7 +92,7 @@ pub fn format(args: CommandArgs) -> Result<ActionStream, ShellError> {
                 &tag,
             )),
         })
-        .to_action_stream())
+        .to_input_stream())
 }
 
 #[cfg(test)]

crates/nu-command/src/commands/date/list_timezone.rs

@@ -3,7 +3,7 @@ use chrono_tz::TZ_VARIANTS;
 use indexmap::IndexMap;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{Dictionary, ReturnSuccess, Signature, UntaggedValue};
+use nu_protocol::{Dictionary, Signature, UntaggedValue};
 
 pub struct Date;
 
@@ -20,7 +20,7 @@ impl WholeStreamCommand for Date {
         "List supported time zones."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         list_timezone(args)
     }
 
@@ -40,7 +40,7 @@ impl WholeStreamCommand for Date {
     }
 }
 
-fn list_timezone(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn list_timezone(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let args = args.evaluate_once()?;
     let tag = args.call_info.name_tag.clone();
 
@@ -52,12 +52,10 @@ fn list_timezone(args: CommandArgs) -> Result<ActionStream, ShellError> {
             UntaggedValue::string(tz.name()).into_value(&tag),
         );
 
-        Ok(ReturnSuccess::Value(
+        Ok(UntaggedValue::Row(Dictionary { entries }).into_value(&tag))
-            UntaggedValue::Row(Dictionary { entries }).into_value(&tag),
-        ))
     });
 
-    Ok(list.into_iter().to_action_stream())
+    Ok(list.into_iter().to_input_stream())
 }
 
 #[cfg(test)]

crates/nu-command/src/commands/date/now.rs

@@ -2,7 +2,7 @@ use crate::prelude::*;
 use chrono::{DateTime, Local};
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{Signature, UntaggedValue};
+use nu_protocol::{Signature, UntaggedValue, Value};
 
 pub struct Date;
 
@@ -19,20 +19,23 @@ impl WholeStreamCommand for Date {
         "Get the current date."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         now(args)
     }
 }
 
-pub fn now(args: CommandArgs) -> Result<ActionStream, ShellError> {
+pub fn date_now(tag: &Tag) -> Value {
-    let args = args.evaluate_once()?;
-    let tag = args.call_info.name_tag.clone();
-
     let now: DateTime<Local> = Local::now();
 
-    let value = UntaggedValue::date(now.with_timezone(now.offset())).into_value(&tag);
+    UntaggedValue::date(now.with_timezone(now.offset())).into_value(tag)
+}
 
-    Ok(ActionStream::one(value))
+pub fn now(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let args = args.evaluate_once()?;
+
+    let value = date_now(&args.call_info.name_tag);
+
+    Ok(OutputStream::one(value))
 }
 
 #[cfg(test)]

crates/nu-command/src/commands/date/to_table.rs

@@ -3,7 +3,7 @@ use chrono::{Datelike, Timelike};
 use indexmap::IndexMap;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{Dictionary, Primitive, ReturnSuccess, Signature, UntaggedValue, Value};
+use nu_protocol::{Dictionary, Primitive, Signature, UntaggedValue, Value};
 
 pub struct Date;
 
@@ -20,7 +20,7 @@ impl WholeStreamCommand for Date {
         "Print the date in a structured table."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         to_table(args)
     }
 
@@ -33,10 +33,14 @@ impl WholeStreamCommand for Date {
     }
 }
 
-fn to_table(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn to_table(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let args = args.evaluate_once()?;
     let tag = args.call_info.name_tag.clone();
-    let input = args.input;
+    let input = if args.input.is_empty() {
+        InputStream::one(crate::commands::date::now::date_now(&tag))
+    } else {
+        args.input
+    };
 
     Ok(input
         .map(move |value| match value {
@@ -79,7 +83,7 @@ fn to_table(args: CommandArgs) -> Result<ActionStream, ShellError> {
 
                 let value = UntaggedValue::Row(Dictionary::from(indexmap)).into_value(&tag);
 
-                ReturnSuccess::value(value)
+                Ok(value)
             }
             _ => Err(ShellError::labeled_error(
                 "Expected a date from pipeline",
@@ -87,7 +91,7 @@ fn to_table(args: CommandArgs) -> Result<ActionStream, ShellError> {
                 &tag,
             )),
         })
-        .to_action_stream())
+        .to_input_stream())
 }
 
 #[cfg(test)]

crates/nu-command/src/commands/date/to_timezone.rs

@@ -2,16 +2,11 @@ use crate::commands::date::parser::{datetime_in_timezone, ParseErrorKind};
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_protocol::{Primitive, Signature, SyntaxShape, UntaggedValue, Value};
 use nu_source::Tagged;
 
 pub struct Date;
 
-#[derive(Deserialize)]
-struct DateToTimeZoneArgs {
-    timezone: Tagged<String>,
-}
-
 impl WholeStreamCommand for Date {
     fn name(&self) -> &str {
         "date to-timezone"
@@ -33,7 +28,7 @@ impl WholeStreamCommand for Date {
         "Use 'date list-timezone' to list all supported time zones."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         to_timezone(args)
     }
 
@@ -58,11 +53,14 @@ impl WholeStreamCommand for Date {
     }
 }
 
-fn to_timezone(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn to_timezone(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let tag = args.call_info.name_tag.clone();
-    let (DateToTimeZoneArgs { timezone }, input) = args.process()?;
+    let args = args.evaluate_once()?;
 
-    Ok(input
+    let timezone: Tagged<String> = args.req(0)?;
+
+    Ok(args
+        .input
         .map(move |value| match value {
             Value {
                 value: UntaggedValue::Primitive(Primitive::Date(dt)),
@@ -71,7 +69,7 @@ fn to_timezone(args: CommandArgs) -> Result<ActionStream, ShellError> {
                 Ok(dt) => {
                     let value = UntaggedValue::date(dt).into_value(&tag);
 
-                    ReturnSuccess::value(value)
+                    Ok(value)
                 }
                 Err(e) => Err(ShellError::labeled_error(
                     error_message(e),
@@ -85,7 +83,7 @@ fn to_timezone(args: CommandArgs) -> Result<ActionStream, ShellError> {
                 &tag,
             )),
         })
-        .to_action_stream())
+        .to_input_stream())
 }
 
 fn error_message(err: ParseErrorKind) -> &'static str {

crates/nu-command/src/commands/date/utc.rs

@@ -1,54 +0,0 @@
-use crate::prelude::*;
-use chrono::{DateTime, Utc};
-use nu_errors::ShellError;
-
-use crate::commands::date::utils::date_to_value;
-use nu_engine::WholeStreamCommand;
-use nu_protocol::Signature;
-
-pub struct Date;
-
-impl WholeStreamCommand for Date {
-    fn name(&self) -> &str {
-        "date utc"
-    }
-
-    fn signature(&self) -> Signature {
-        Signature::build("date utc")
-    }
-
-    fn usage(&self) -> &str {
-        "return the current date in utc."
-    }
-
-    fn run_with_actions(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
-        utc(args)
-    }
-}
-
-pub fn utc(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let args = args.evaluate_once()?;
-    let tag = args.call_info.name_tag.clone();
-
-    let no_fmt = "".to_string();
-
-    let value = {
-        let local: DateTime<Utc> = Utc::now();
-        date_to_value(local, tag, no_fmt)
-    };
-
-    Ok(OutputStream::one(value))
-}
-
-#[cfg(test)]
-mod tests {
-    use super::Date;
-    use super::ShellError;
-
-    #[test]
-    fn examples_work_as_expected() -> Result<(), ShellError> {
-        use crate::examples::test as test_examples;
-
-        test_examples(Date {})
-    }
-}

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

@@ -1,10 +1,9 @@
 use crate::prelude::*;
-use nu_engine::basic_evaluation_context;
 use nu_engine::whole_stream_command;
 use std::error::Error;
 
 pub fn create_default_context(interactive: bool) -> Result<EvaluationContext, Box<dyn Error>> {
-    let context = basic_evaluation_context()?;
+    let context = EvaluationContext::basic();
 
     {
         use crate::commands::*;
@@ -14,6 +13,7 @@ pub fn create_default_context(interactive: bool) -> Result<EvaluationContext, Bo
             whole_stream_command(NuPlugin),
             whole_stream_command(Let),
             whole_stream_command(LetEnv),
+            whole_stream_command(LoadEnv),
             whole_stream_command(Def),
             whole_stream_command(Source),
             // System/file operations
@@ -89,7 +89,6 @@ pub fn create_default_context(interactive: bool) -> Result<EvaluationContext, Bo
             whole_stream_command(StrUpcase),
             whole_stream_command(StrCapitalize),
             whole_stream_command(StrFindReplace),
-            whole_stream_command(StrFrom),
             whole_stream_command(StrSubstring),
             whole_stream_command(StrToDatetime),
             whole_stream_command(StrContains),
@@ -122,7 +121,9 @@ pub fn create_default_context(interactive: bool) -> Result<EvaluationContext, Bo
             whole_stream_command(Update),
             whole_stream_command(Insert),
             whole_stream_command(Into),
+            whole_stream_command(IntoBinary),
             whole_stream_command(IntoInt),
+            whole_stream_command(IntoString),
             whole_stream_command(SplitBy),
             // Row manipulation
             whole_stream_command(All),
@@ -157,6 +158,7 @@ pub fn create_default_context(interactive: bool) -> Result<EvaluationContext, Bo
             whole_stream_command(EachGroup),
             whole_stream_command(EachWindow),
             whole_stream_command(Empty),
+            whole_stream_command(ForIn),
             // Table manipulation
             whole_stream_command(Flatten),
             whole_stream_command(Move),
@@ -239,6 +241,7 @@ pub fn create_default_context(interactive: bool) -> Result<EvaluationContext, Bo
             whole_stream_command(PathExpand),
             whole_stream_command(PathJoin),
             whole_stream_command(PathParse),
+            whole_stream_command(PathRelativeTo),
             whole_stream_command(PathSplit),
             whole_stream_command(PathType),
             // Url
@@ -250,6 +253,31 @@ pub fn create_default_context(interactive: bool) -> Result<EvaluationContext, Bo
             whole_stream_command(Seq),
             whole_stream_command(SeqDates),
             whole_stream_command(TermSize),
+            //Dataframe commands
+            #[cfg(feature = "dataframe")]
+            whole_stream_command(DataFrame),
+            #[cfg(feature = "dataframe")]
+            whole_stream_command(DataFrameConvert),
+            #[cfg(feature = "dataframe")]
+            whole_stream_command(DataFrameLoad),
+            #[cfg(feature = "dataframe")]
+            whole_stream_command(DataFrameList),
+            #[cfg(feature = "dataframe")]
+            whole_stream_command(DataFrameGroupBy),
+            #[cfg(feature = "dataframe")]
+            whole_stream_command(DataFrameAggregate),
+            #[cfg(feature = "dataframe")]
+            whole_stream_command(DataFrameShow),
+            #[cfg(feature = "dataframe")]
+            whole_stream_command(DataFrameSample),
+            #[cfg(feature = "dataframe")]
+            whole_stream_command(DataFrameJoin),
+            #[cfg(feature = "dataframe")]
+            whole_stream_command(DataFrameDrop),
+            #[cfg(feature = "dataframe")]
+            whole_stream_command(DataFrameSelect),
+            #[cfg(feature = "dataframe")]
+            whole_stream_command(DataFrameDTypes),
         ]);
 
         #[cfg(feature = "clipboard-cli")]

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

@@ -2,14 +2,16 @@ use crate::prelude::*;
 use nu_engine::run_block;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{hir::CapturedBlock, hir::ExternalRedirection, Signature, SyntaxShape, Value};
+use nu_protocol::{
+    hir::CapturedBlock, hir::ExternalRedirection, Signature, SyntaxShape, UntaggedValue, Value,
+};
 
 pub struct Do;
 
-#[derive(Deserialize, Debug)]
 struct DoArgs {
     block: CapturedBlock,
     ignore_errors: bool,
+    rest: Vec<Value>,
 }
 
 impl WholeStreamCommand for Do {
@@ -21,17 +23,18 @@ impl WholeStreamCommand for Do {
         Signature::build("do")
             .required("block", SyntaxShape::Block, "the block to run ")
             .switch(
-                "ignore_errors",
+                "ignore-errors",
                 "ignore errors as the block runs",
                 Some('i'),
             )
+            .rest(SyntaxShape::Any, "the parameter(s) for the block")
     }
 
     fn usage(&self) -> &str {
         "Runs a block, optionally ignoring errors."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         do_(args)
     }
 
@@ -47,32 +50,36 @@ impl WholeStreamCommand for Do {
                 example: r#"do -i { thisisnotarealcommand }"#,
                 result: Some(vec![]),
             },
+            Example {
+                description: "Run the block with a parameter",
+                example: r#"do { |x| $x + 100 } 55"#,
+                result: Some(vec![UntaggedValue::int(155).into()]),
+            },
         ]
     }
 }
 
-fn do_(raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn do_(raw_args: CommandArgs) -> Result<OutputStream, ShellError> {
     let external_redirection = raw_args.call_info.args.external_redirection;
 
     let context = EvaluationContext::from_args(&raw_args);
-    let (
+    let args = raw_args.evaluate_once()?;
-        DoArgs {
+    let do_args = DoArgs {
-            ignore_errors,
+        block: args.req(0)?,
-            mut block,
+        ignore_errors: args.has_flag("ignore-errors"),
-        },
+        rest: args.rest(1)?,
-        input,
+    };
-    ) = raw_args.process()?;
 
     let block_redirection = match external_redirection {
         ExternalRedirection::None => {
-            if ignore_errors {
+            if do_args.ignore_errors {
                 ExternalRedirection::Stderr
             } else {
                 ExternalRedirection::None
             }
         }
         ExternalRedirection::Stdout => {
-            if ignore_errors {
+            if do_args.ignore_errors {
                 ExternalRedirection::StdoutAndStderr
             } else {
                 ExternalRedirection::Stdout
@@ -81,14 +88,30 @@ fn do_(raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
         x => x,
     };
 
-    if let Some(block) = std::sync::Arc::<nu_protocol::hir::Block>::get_mut(&mut block.block) {
-        block.set_redirect(block_redirection);
-    }
     context.scope.enter_scope();
-    let result = run_block(&block.block, &context, input);
+
+    context.scope.add_vars(&do_args.block.captured.entries);
+
+    for (param, value) in do_args
+        .block
+        .block
+        .params
+        .positional
+        .iter()
+        .zip(do_args.rest)
+    {
+        context.scope.add_var(param.0.name(), value.clone());
+    }
+
+    let result = run_block(
+        &do_args.block.block,
+        &context,
+        args.input,
+        block_redirection,
+    );
     context.scope.exit_scope();
 
-    if ignore_errors {
+    if do_args.ignore_errors {
         // To properly ignore errors we need to redirect stderr, consume it, and remove
         // any errors we see in the process.
 
@@ -96,12 +119,12 @@ fn do_(raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
             Ok(mut stream) => {
                 let output = stream.drain_vec();
                 context.clear_errors();
-                Ok(output.into_iter().to_action_stream())
+                Ok(output.into_iter().to_output_stream())
             }
-            Err(_) => Ok(ActionStream::empty()),
+            Err(_) => Ok(OutputStream::empty()),
         }
     } else {
-        result.map(|x| x.to_action_stream())
+        result.map(|x| x.to_output_stream())
     }
 }
 

crates/nu-command/src/commands/drop/column.rs

@@ -2,16 +2,11 @@ use crate::prelude::*;
 use nu_data::base::select_fields;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, Signature, SyntaxShape};
+use nu_protocol::{Signature, SyntaxShape};
 use nu_source::Tagged;
 
 pub struct SubCommand;
 
-#[derive(Deserialize)]
-pub struct Arguments {
-    columns: Option<Tagged<u64>>,
-}
-
 impl WholeStreamCommand for SubCommand {
     fn name(&self) -> &str {
         "drop column"
@@ -29,7 +24,7 @@ impl WholeStreamCommand for SubCommand {
         "Remove the last number of columns. If you want to remove columns by name, try 'reject'."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         drop(args)
     }
 
@@ -47,8 +42,9 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-fn drop(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn drop(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let (Arguments { columns }, input) = args.process()?;
+    let args = args.evaluate_once()?;
+    let columns: Option<Tagged<u64>> = args.opt(0)?;
 
     let to_drop = if let Some(quantity) = columns {
         *quantity as usize
@@ -56,7 +52,8 @@ fn drop(args: CommandArgs) -> Result<ActionStream, ShellError> {
         1
     };
 
-    Ok(input
+    Ok(args
+        .input
         .map(move |item| {
             let headers = item.data_descriptors();
 
@@ -66,10 +63,9 @@ fn drop(args: CommandArgs) -> Result<ActionStream, ShellError> {
                 n => &headers[..n - to_drop],
             };
 
-            select_fields(&item, descs, item.tag())
+            Ok(select_fields(&item, descs, item.tag()))
         })
-        .map(ReturnSuccess::value)
+        .to_input_stream())
-        .to_action_stream())
 }
 
 #[cfg(test)]

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

@@ -6,11 +6,6 @@ use nu_source::Tagged;
 
 pub struct Command;
 
-#[derive(Deserialize)]
-pub struct Arguments {
-    rows: Option<Tagged<u64>>,
-}
-
 impl WholeStreamCommand for Command {
     fn name(&self) -> &str {
         "drop"
@@ -28,7 +23,7 @@ impl WholeStreamCommand for Command {
         "Remove the last number of rows or columns."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         drop(args)
     }
 
@@ -51,9 +46,10 @@ impl WholeStreamCommand for Command {
     }
 }
 
-fn drop(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn drop(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let (Arguments { rows }, input) = args.process()?;
+    let args = args.evaluate_once()?;
-    let v: Vec<_> = input.into_vec();
+    let rows: Option<Tagged<u64>> = args.opt(0)?;
+    let v: Vec<_> = args.input.into_vec();
 
     let rows_to_drop = if let Some(quantity) = rows {
         *quantity as usize
@@ -62,7 +58,7 @@ fn drop(args: CommandArgs) -> Result<ActionStream, ShellError> {
     };
 
     Ok(if rows_to_drop == 0 {
-        v.into_iter().to_action_stream()
+        v.into_iter().map(Ok).to_input_stream()
     } else {
         let k = if v.len() < rows_to_drop {
             0
@@ -70,8 +66,8 @@ fn drop(args: CommandArgs) -> Result<ActionStream, ShellError> {
             v.len() - rows_to_drop
         };
 
-        let iter = v.into_iter().take(k);
+        let iter = v.into_iter().map(Ok).take(k);
 
-        iter.to_action_stream()
+        iter.to_input_stream()
     })
 }

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

@@ -85,7 +85,7 @@ impl WholeStreamCommand for Du {
 
 fn du(args: CommandArgs) -> Result<ActionStream, ShellError> {
     let tag = args.call_info.name_tag.clone();
-    let ctrl_c = args.ctrl_c.clone();
+    let ctrl_c = args.ctrl_c();
     let ctrl_c_copy = ctrl_c.clone();
 
     let (args, _): (DuArgs, _) = args.process()?;

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

@@ -4,7 +4,8 @@ use nu_engine::WholeStreamCommand;
 
 use nu_errors::ShellError;
 use nu_protocol::{
-    hir::CapturedBlock, Signature, SyntaxShape, TaggedDictBuilder, UntaggedValue, Value,
+    hir::{CapturedBlock, ExternalRedirection},
+    Signature, SyntaxShape, TaggedDictBuilder, UntaggedValue, Value,
 };
 
 pub struct Each;
@@ -41,7 +42,7 @@ impl WholeStreamCommand for Each {
             },
             Example {
                 description: "Echo the square of each integer",
-                example: "echo [1 2 3] | each { echo $(= $it * $it) }",
+                example: "echo [1 2 3] | each { echo ($it * $it) }",
                 result: Some(vec![
                     UntaggedValue::int(1).into(),
                     UntaggedValue::int(4).into(),
@@ -51,9 +52,18 @@ impl WholeStreamCommand for Each {
             Example {
                 description: "Number each item and echo a message",
                 example:
-                    "echo ['bob' 'fred'] | each --numbered { echo `{{$it.index}} is {{$it.item}}` }",
+                    "echo ['bob' 'fred'] | each --numbered { echo $\"($it.index) is ($it.item)\" }",
                 result: Some(vec![Value::from("0 is bob"), Value::from("1 is fred")]),
             },
+            Example {
+                description: "Name the block variable that each uses",
+                example: "[1, 2, 3] | each {|x| $x + 100}",
+                result: Some(vec![
+                    UntaggedValue::int(101).into(),
+                    UntaggedValue::int(102).into(),
+                    UntaggedValue::int(103).into(),
+                ]),
+            },
         ]
     }
 }
@@ -62,6 +72,7 @@ pub fn process_row(
     captured_block: Arc<Box<CapturedBlock>>,
     context: Arc<EvaluationContext>,
     input: Value,
+    external_redirection: ExternalRedirection,
 ) -> Result<OutputStream, ShellError> {
     let input_clone = input.clone();
     // When we process a row, we need to know whether the block wants to have the contents of the row as
@@ -77,16 +88,18 @@ pub fn process_row(
     context.scope.enter_scope();
     context.scope.add_vars(&captured_block.captured.entries);
 
-    if !captured_block.block.params.positional.is_empty() {
+    if let Some((arg, _)) = captured_block.block.params.positional.first() {
-        // FIXME: add check for more than parameter, once that's supported
+        context.scope.add_var(arg.name(), input);
-        context
-            .scope
-            .add_var(captured_block.block.params.positional[0].0.name(), input);
     } else {
         context.scope.add_var("$it", input);
     }
 
-    let result = run_block(&captured_block.block, &*context, input_stream);
+    let result = run_block(
+        &captured_block.block,
+        &*context,
+        input_stream,
+        external_redirection,
+    );
 
     context.scope.exit_scope();
 
@@ -95,7 +108,7 @@ pub fn process_row(
 
 pub(crate) fn make_indexed_item(index: usize, item: Value) -> Value {
     let mut dict = TaggedDictBuilder::new(item.tag());
-    dict.insert_untagged("index", UntaggedValue::int(index));
+    dict.insert_untagged("index", UntaggedValue::int(index as i64));
     dict.insert_value("item", item);
 
     dict.into_value()
@@ -103,6 +116,7 @@ pub(crate) fn make_indexed_item(index: usize, item: Value) -> Value {
 
 fn each(raw_args: CommandArgs) -> Result<OutputStream, ShellError> {
     let context = Arc::new(EvaluationContext::from_args(&raw_args));
+    let external_redirection = raw_args.call_info.args.external_redirection;
     let args = raw_args.evaluate_once()?;
 
     let block: CapturedBlock = args.req(0)?;
@@ -119,7 +133,7 @@ fn each(raw_args: CommandArgs) -> Result<OutputStream, ShellError> {
                 let context = context.clone();
                 let row = make_indexed_item(input.0, input.1);
 
-                match process_row(block, context, row) {
+                match process_row(block, context, row, external_redirection) {
                     Ok(s) => s,
                     Err(e) => OutputStream::one(Value::error(e)),
                 }
@@ -133,7 +147,7 @@ fn each(raw_args: CommandArgs) -> Result<OutputStream, ShellError> {
                 let block = block.clone();
                 let context = context.clone();
 
-                match process_row(block, context, input) {
+                match process_row(block, context, input, external_redirection) {
                     Ok(s) => s,
                     Err(e) => OutputStream::one(Value::error(e)),
                 }

crates/nu-command/src/commands/each/group.rs

@@ -2,19 +2,14 @@ use crate::commands::each::process_row;
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{hir::CapturedBlock, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_protocol::{
+    hir::{CapturedBlock, ExternalRedirection},
+    Signature, SyntaxShape, UntaggedValue, Value,
+};
 use nu_source::Tagged;
-use serde::Deserialize;
 
 pub struct EachGroup;
 
-#[derive(Deserialize)]
-pub struct EachGroupArgs {
-    group_size: Tagged<usize>,
-    block: CapturedBlock,
-    //numbered: Tagged<bool>,
-}
-
 impl WholeStreamCommand for EachGroup {
     fn name(&self) -> &str {
         "each group"
@@ -42,19 +37,24 @@ impl WholeStreamCommand for EachGroup {
         }]
     }
 
-    fn run_with_actions(&self, raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, raw_args: CommandArgs) -> Result<OutputStream, ShellError> {
         let context = Arc::new(EvaluationContext::from_args(&raw_args));
-        let (each_args, input): (EachGroupArgs, _) = raw_args.process()?;
+        let external_redirection = raw_args.call_info.args.external_redirection;
-        let block = Arc::new(Box::new(each_args.block));
+        let args = raw_args.evaluate_once()?;
+
+        let group_size: Tagged<usize> = args.req(0)?;
+        let block: CapturedBlock = args.req(1)?;
+        let block = Arc::new(Box::new(block));
 
         let each_group_iterator = EachGroupIterator {
             block,
             context,
-            group_size: each_args.group_size.item,
+            group_size: group_size.item,
-            input,
+            input: args.input,
+            external_redirection,
         };
 
-        Ok(each_group_iterator.flatten().to_action_stream())
+        Ok(each_group_iterator.flatten().map(Ok).to_input_stream())
     }
 }
 
@@ -63,6 +63,7 @@ struct EachGroupIterator {
     context: Arc<EvaluationContext>,
     group_size: usize,
     input: InputStream,
+    external_redirection: ExternalRedirection,
 }
 
 impl Iterator for EachGroupIterator {
@@ -89,6 +90,7 @@ impl Iterator for EachGroupIterator {
             group,
             self.block.clone(),
             self.context.clone(),
+            self.external_redirection,
         ))
     }
 }
@@ -97,13 +99,14 @@ pub(crate) fn run_block_on_vec(
     input: Vec<Value>,
     block: Arc<Box<CapturedBlock>>,
     context: Arc<EvaluationContext>,
+    external_redirection: ExternalRedirection,
 ) -> OutputStream {
     let value = Value {
         value: UntaggedValue::Table(input),
         tag: Tag::unknown(),
     };
 
-    match process_row(block, context, value) {
+    match process_row(block, context, value, external_redirection) {
         Ok(s) => {
             // We need to handle this differently depending on whether process_row
             // returned just 1 value or if it returned multiple as a stream.

crates/nu-command/src/commands/each/window.rs

@@ -5,17 +5,9 @@ use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
 use nu_protocol::{hir::CapturedBlock, Primitive, Signature, SyntaxShape, UntaggedValue};
 use nu_source::Tagged;
-use serde::Deserialize;
 
 pub struct EachWindow;
 
-#[derive(Deserialize)]
-pub struct EachWindowArgs {
-    window_size: Tagged<usize>,
-    block: CapturedBlock,
-    stride: Option<Tagged<usize>>,
-}
-
 impl WholeStreamCommand for EachWindow {
     fn name(&self) -> &str {
         "each window"
@@ -49,21 +41,29 @@ impl WholeStreamCommand for EachWindow {
         }]
     }
 
-    fn run_with_actions(&self, raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, raw_args: CommandArgs) -> Result<OutputStream, ShellError> {
         let context = Arc::new(EvaluationContext::from_args(&raw_args));
-        let (each_args, mut input): (EachWindowArgs, _) = raw_args.process()?;
+        let external_redirection = raw_args.call_info.args.external_redirection;
-        let block = Arc::new(Box::new(each_args.block));
 
-        let mut window: Vec<_> = input
+        let mut args = raw_args.evaluate_once()?;
+        let window_size: Tagged<usize> = args.req(0)?;
+        let block: CapturedBlock = args.req(1)?;
+        let stride: Option<Tagged<usize>> = args.get_flag("stride")?;
+
+        let block = Arc::new(Box::new(block));
+
+        let mut window: Vec<_> = args
+            .input
             .by_ref()
-            .take(*each_args.window_size - 1)
+            .take(*window_size - 1)
             .collect::<Vec<_>>();
 
         // `window` must start with dummy values, which will be removed on the first iteration
-        let stride = each_args.stride.map(|x| *x).unwrap_or(1);
+        let stride = stride.map(|x| *x).unwrap_or(1);
         window.insert(0, UntaggedValue::Primitive(Primitive::Nothing).into());
 
-        Ok(input
+        Ok(args
+            .input
             .enumerate()
             .map(move |(i, input)| {
                 // This would probably be more efficient if `last` was a VecDeque
@@ -76,14 +76,20 @@ impl WholeStreamCommand for EachWindow {
                 let local_window = window.clone();
 
                 if i % stride == 0 {
-                    Some(run_block_on_vec(local_window, block, context))
+                    Some(run_block_on_vec(
+                        local_window,
+                        block,
+                        context,
+                        external_redirection,
+                    ))
                 } else {
                     None
                 }
             })
-            .filter_map(|x| x)
             .flatten()
-            .to_action_stream())
+            .flatten()
+            .map(Ok)
+            .to_input_stream())
     }
 }
 

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

@@ -1,5 +1,4 @@
 use crate::prelude::*;
-use bigdecimal::Zero;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
 use nu_protocol::hir::Operator;
@@ -40,23 +39,27 @@ impl WholeStreamCommand for Echo {
     }
 }
 
+pub fn expand_value_to_stream(v: Value) -> InputStream {
+    match v {
+        Value {
+            value: UntaggedValue::Table(table),
+            ..
+        } => InputStream::from_stream(table.into_iter()),
+        Value {
+            value: UntaggedValue::Primitive(Primitive::Range(range)),
+            tag,
+        } => InputStream::from_stream(RangeIterator::new(*range, tag)),
+        x => InputStream::one(x),
+    }
+}
+
 fn echo(args: CommandArgs) -> Result<InputStream, ShellError> {
     let args = args.evaluate_once()?;
     let rest: Vec<Value> = args.rest(0)?;
 
     let stream = rest.into_iter().map(|i| match i.as_string() {
-        Ok(s) => InputStream::one(UntaggedValue::string(s).into_value(i.tag.clone())),
+        Ok(s) => InputStream::one(UntaggedValue::string(s).into_value(i.tag)),
-        _ => match i {
+        _ => expand_value_to_stream(i),
-            Value {
-                value: UntaggedValue::Table(table),
-                ..
-            } => InputStream::from_stream(table.into_iter()),
-            Value {
-                value: UntaggedValue::Primitive(Primitive::Range(range)),
-                tag,
-            } => InputStream::from_stream(RangeIterator::new(*range, tag)),
-            x => InputStream::one(x),
-        },
     });
 
     Ok(InputStream::from_stream(stream.flatten()))
@@ -81,7 +84,7 @@ impl RangeIterator {
         };
 
         let end = match range.to.0.item {
-            Primitive::Nothing => Primitive::Int(u64::MAX.into()),
+            Primitive::Nothing => Primitive::Int(i64::MAX),
             x => x,
         };
 
@@ -121,11 +124,11 @@ impl Iterator for RangeIterator {
                 (
                     UntaggedValue::Primitive(Primitive::Decimal(x)),
                     UntaggedValue::Primitive(Primitive::Int(y)),
-                ) => x.cmp(&(BigDecimal::zero() + y)),
+                ) => x.cmp(&(BigDecimal::from(*y))),
                 (
                     UntaggedValue::Primitive(Primitive::Int(x)),
                     UntaggedValue::Primitive(Primitive::Decimal(y)),
-                ) => (BigDecimal::zero() + x).cmp(y),
+                ) => (BigDecimal::from(*x)).cmp(y),
                 _ => {
                     self.done = true;
                     return Some(

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

@@ -3,8 +3,8 @@ use nu_engine::run_block;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
 use nu_protocol::{
-    hir::CapturedBlock, ColumnPath, Primitive, ReturnSuccess, Signature, SyntaxShape,
+    hir::CapturedBlock, hir::ExternalRedirection, ColumnPath, Primitive, ReturnSuccess, Signature,
-    UntaggedValue, Value,
+    SyntaxShape, UntaggedValue, Value,
 };
 
 use crate::utils::arguments::arguments;
@@ -63,7 +63,7 @@ impl WholeStreamCommand for Command {
                 ),
             },Example {
                 description: "use a block if setting the empty cell contents is wanted",
-                example: "echo [[2020/04/16 2020/07/10 2020/11/16]; ['' [27] [37]]] | empty? 2020/04/16 { = [33 37] }",
+                example: "echo [[2020/04/16 2020/07/10 2020/11/16]; ['' [27] [37]]] | empty? 2020/04/16 { [33 37] }",
                 result: Some(
                     vec![
                         UntaggedValue::row(indexmap! {
@@ -140,9 +140,16 @@ fn process_row(
 
         context.scope.enter_scope();
         context.scope.add_vars(&default_block.captured.entries);
-        context.scope.add_var("$it", input.clone());
+        if let Some((arg, _)) = default_block.block.params.positional.first() {
+            context.scope.add_var(arg.name(), input.clone());
+        }
 
-        let stream = run_block(&default_block.block, &*context, input_stream);
+        let stream = run_block(
+            &default_block.block,
+            &*context,
+            input_stream,
+            ExternalRedirection::Stdout,
+        );
         context.scope.exit_scope();
 
         let mut stream = stream?;

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

@@ -11,12 +11,6 @@ use std::path::PathBuf;
 
 pub struct Enter;
 
-#[derive(Deserialize)]
-pub struct EnterArgs {
-    location: Tagged<PathBuf>,
-    encoding: Option<Tagged<String>>,
-}
-
 impl WholeStreamCommand for Enter {
     fn name(&self) -> &str {
         "enter"
@@ -75,16 +69,15 @@ documentation link at https://docs.rs/encoding_rs/0.8.28/encoding_rs/#statics"#
     }
 }
 
-fn enter(raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn enter(args: CommandArgs) -> Result<ActionStream, ShellError> {
-    let scope = raw_args.scope.clone();
+    let head = args.call_info.args.head.clone();
-    let shell_manager = raw_args.shell_manager.clone();
+    let context = args.context.clone();
-    let head = raw_args.call_info.args.head.clone();
+    let scope = args.scope().clone();
-    let ctrl_c = raw_args.ctrl_c.clone();
+    let path = args.context.shell_manager.path();
-    let configs = raw_args.configs.clone();
+    let args = args.evaluate_once()?;
-    let current_errors = raw_args.current_errors.clone();
+
-    let host = raw_args.host.clone();
+    let location: Tagged<PathBuf> = args.req(0)?;
-    let tag = raw_args.call_info.name_tag.clone();
+    let encoding: Option<Tagged<String>> = args.get_flag("encoding")?;
-    let (EnterArgs { location, encoding }, _) = raw_args.process()?;
     let location_string = location.display().to_string();
 
     if location.is_dir() {
@@ -93,7 +86,7 @@ fn enter(raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
         )))
     } else {
         // If it's a file, attempt to open the file as a value and enter it
-        let cwd = shell_manager.path();
+        let cwd = path;
 
         let full_path = std::path::PathBuf::from(cwd);
         let span = location.span();
@@ -110,12 +103,9 @@ fn enter(raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
                 if let Some(extension) = file_extension {
                     let command_name = format!("from {}", extension);
                     if let Some(converter) = scope.get_command(&command_name) {
-                        let new_args = RawCommandArgs {
+                        let tag = tagged_contents.tag.clone();
-                            host,
+                        let new_args = CommandArgs {
-                            ctrl_c,
+                            context,
-                            configs,
-                            current_errors,
-                            shell_manager,
                             call_info: UnevaluatedCallInfo {
                                 args: nu_protocol::hir::Call {
                                     head,
@@ -124,13 +114,11 @@ fn enter(raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
                                     span: Span::unknown(),
                                     external_redirection: ExternalRedirection::Stdout,
                                 },
-                                name_tag: tag,
+                                name_tag: tag.clone(),
                             },
-                            scope,
+                            input: InputStream::one(tagged_contents),
                         };
-                        let tag = tagged_contents.tag.clone();
+                        let mut result = converter.run(new_args)?;
-                        let mut result =
-                            converter.run(new_args.with_input(vec![tagged_contents]))?;
                         let result_vec: Vec<Value> = result.drain_vec();
                         Ok(result_vec
                             .into_iter()

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

@@ -39,12 +39,12 @@ impl WholeStreamCommand for Command {
             },
             Example {
                 description: "flatten a column having a nested table",
-                example: "echo [[origin, people]; [Ecuador, $(echo [[name, meal]; ['Andres', 'arepa']])]] | flatten | get meal",
+                example: "echo [[origin, people]; [Ecuador, (echo [[name, meal]; ['Andres', 'arepa']])]] | flatten | get meal",
                 result: Some(vec![Value::from("arepa")]),
             },
             Example {
                 description: "restrict the flattening by passing column names",
-                example: "echo [[origin, crate, versions]; [World, $(echo [[name]; ['nu-cli']]), ['0.21', '0.22']]] | flatten versions | last | get versions",
+                example: "echo [[origin, crate, versions]; [World, (echo [[name]; ['nu-cli']]), ['0.21', '0.22']]] | flatten versions | last | get versions",
                 result: Some(vec![Value::from("0.22")]),
             }
         ]

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

@@ -0,0 +1,174 @@
+use crate::prelude::*;
+use nu_engine::{evaluate_baseline_expr, run_block};
+use nu_engine::{FromValue, WholeStreamCommand};
+
+use nu_errors::ShellError;
+use nu_protocol::{
+    hir::{CapturedBlock, ExternalRedirection},
+    Signature, SyntaxShape, TaggedDictBuilder, UntaggedValue, Value,
+};
+
+pub struct ForIn;
+
+impl WholeStreamCommand for ForIn {
+    fn name(&self) -> &str {
+        "for"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("for")
+            .required("var", SyntaxShape::String, "the name of the variable")
+            .required("in", SyntaxShape::String, "the word 'in'")
+            .required("value", SyntaxShape::Any, "the value we want to iterate")
+            .required("block", SyntaxShape::Block, "the block to run on each item")
+            .switch(
+                "numbered",
+                "returned a numbered item ($it.index and $it.item)",
+                Some('n'),
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "Run a block on each row of the table."
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        for_in(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Echo the square of each integer",
+                example: "for x in [1 2 3] { $x * $x }",
+                result: Some(vec![
+                    UntaggedValue::int(1).into(),
+                    UntaggedValue::int(4).into(),
+                    UntaggedValue::int(9).into(),
+                ]),
+            },
+            Example {
+                description: "Work with elements of a range",
+                example: "for $x in 1..3 { $x }",
+                result: Some(vec![
+                    UntaggedValue::int(1).into(),
+                    UntaggedValue::int(2).into(),
+                    UntaggedValue::int(3).into(),
+                ]),
+            },
+            Example {
+                description: "Number each item and echo a message",
+                example: "for $it in ['bob' 'fred'] --numbered { $\"($it.index) is ($it.item)\" }",
+                result: Some(vec![Value::from("0 is bob"), Value::from("1 is fred")]),
+            },
+        ]
+    }
+}
+
+pub fn process_row(
+    captured_block: Arc<Box<CapturedBlock>>,
+    context: Arc<EvaluationContext>,
+    input: Value,
+    var_name: &str,
+    external_redirection: ExternalRedirection,
+) -> Result<OutputStream, ShellError> {
+    let input_clone = input.clone();
+    // When we process a row, we need to know whether the block wants to have the contents of the row as
+    // a parameter to the block (so it gets assigned to a variable that can be used inside the block) or
+    // if it wants the contents as as an input stream
+
+    let input_stream = if !captured_block.block.params.positional.is_empty() {
+        InputStream::empty()
+    } else {
+        vec![Ok(input_clone)].into_iter().to_input_stream()
+    };
+
+    context.scope.enter_scope();
+    context.scope.add_vars(&captured_block.captured.entries);
+
+    context.scope.add_var(var_name, input);
+
+    let result = run_block(
+        &captured_block.block,
+        &*context,
+        input_stream,
+        external_redirection,
+    );
+
+    context.scope.exit_scope();
+
+    result
+}
+
+pub(crate) fn make_indexed_item(index: usize, item: Value) -> Value {
+    let mut dict = TaggedDictBuilder::new(item.tag());
+    dict.insert_untagged("index", UntaggedValue::int(index as i64));
+    dict.insert_value("item", item);
+
+    dict.into_value()
+}
+
+fn for_in(raw_args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let context = Arc::new(EvaluationContext::from_args(&raw_args));
+    let external_redirection = raw_args.call_info.args.external_redirection;
+    //let args = raw_args.evaluate_once()?;
+
+    let numbered: bool = raw_args.call_info.switch_present("numbered");
+    let positional = raw_args
+        .call_info
+        .args
+        .positional
+        .expect("Internal error: type checker should require args");
+
+    let var_name = positional[0].var_name()?;
+    let rhs = evaluate_baseline_expr(&positional[2], &context)?;
+
+    let block: CapturedBlock =
+        FromValue::from_value(&evaluate_baseline_expr(&positional[3], &context)?)?;
+
+    let input = crate::commands::echo::expand_value_to_stream(rhs);
+    let block = Arc::new(Box::new(block));
+
+    if numbered {
+        Ok(input
+            .enumerate()
+            .map(move |input| {
+                let block = block.clone();
+                let context = context.clone();
+                let row = make_indexed_item(input.0, input.1);
+
+                match process_row(block, context, row, &var_name, external_redirection) {
+                    Ok(s) => s,
+                    Err(e) => OutputStream::one(Value::error(e)),
+                }
+            })
+            .flatten()
+            .to_output_stream())
+    } else {
+        Ok(input
+            .map(move |input| {
+                let block = block.clone();
+                let context = context.clone();
+
+                match process_row(block, context, input, &var_name, external_redirection) {
+                    Ok(s) => s,
+                    Err(e) => OutputStream::one(Value::error(e)),
+                }
+            })
+            .flatten()
+            .to_output_stream())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::ForIn;
+    use super::ShellError;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test as test_examples;
+
+        test_examples(ForIn {})
+    }
+}

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

@@ -2,17 +2,12 @@ use crate::prelude::*;
 use nu_engine::evaluate_baseline_expr;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, UntaggedValue};
+use nu_protocol::{Signature, SyntaxShape, UntaggedValue};
 use nu_source::Tagged;
 use std::borrow::Borrow;
 
 pub struct Format;
 
-#[derive(Deserialize)]
-pub struct FormatArgs {
-    pattern: Tagged<String>,
-}
-
 impl WholeStreamCommand for Format {
     fn name(&self) -> &str {
         "format"
@@ -30,7 +25,7 @@ impl WholeStreamCommand for Format {
         "Format columns into a string using a simple pattern."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         format_command(args)
     }
 
@@ -43,14 +38,16 @@ impl WholeStreamCommand for Format {
     }
 }
 
-fn format_command(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn format_command(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let ctx = Arc::new(EvaluationContext::from_args(&args));
-    let (FormatArgs { pattern }, input) = args.process()?;
+    let args = args.evaluate_once()?;
+    let pattern: Tagged<String> = args.req(0)?;
 
     let format_pattern = format(&pattern);
     let commands = Arc::new(format_pattern);
 
-    Ok(input
+    Ok(args
+        .input
         .map(move |value| {
             let mut output = String::new();
             let commands = commands.clone();
@@ -82,9 +79,9 @@ fn format_command(args: CommandArgs) -> Result<ActionStream, ShellError> {
                 }
             }
 
-            ReturnSuccess::value(UntaggedValue::string(output).into_untagged_value())
+            Ok(UntaggedValue::string(output).into_untagged_value())
         })
-        .to_action_stream())
+        .to_input_stream())
 }
 
 #[derive(Debug)]

crates/nu-command/src/commands/format/format_filesize.rs

@@ -2,20 +2,12 @@ use crate::prelude::*;
 use nu_data::base::shape::InlineShape;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{
+use nu_protocol::{ColumnPath, Primitive::Filesize, Signature, SyntaxShape, UntaggedValue, Value};
-    ColumnPath, Primitive::Filesize, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
-};
 use nu_source::Tagged;
 use nu_value_ext::get_data_by_column_path;
 
 pub struct FileSize;
 
-#[derive(Deserialize)]
-pub struct Arguments {
-    field: ColumnPath,
-    format: Tagged<String>,
-}
-
 impl WholeStreamCommand for FileSize {
     fn name(&self) -> &str {
         "format filesize"
@@ -39,7 +31,7 @@ impl WholeStreamCommand for FileSize {
         "Converts a column of filesizes to some specified format"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         filesize(args)
     }
 
@@ -63,50 +55,55 @@ fn process_row(
     input: Value,
     format: Tagged<String>,
     field: Arc<ColumnPath>,
-) -> Result<ActionStream, ShellError> {
+) -> Result<Value, ShellError> {
-    Ok({
+    let replace_for = get_data_by_column_path(&input, &field, move |_, _, error| error);
-        let replace_for = get_data_by_column_path(&input, &field, move |_, _, error| error);
+    match replace_for {
-        match replace_for {
+        Ok(s) => {
-            Ok(s) => {
+            if let Value {
-                if let Value {
+                value: UntaggedValue::Primitive(Filesize(fs)),
-                    value: UntaggedValue::Primitive(Filesize(fs)),
+                ..
-                    ..
+            } = s
-                } = s
+            {
-                {
+                let byte_format = InlineShape::format_bytes(fs, Some(&format.item));
-                    let byte_format = InlineShape::format_bytes(&fs, Some(&format.item));
+                let byte_value = Value::from(byte_format.1);
-                    let byte_value = Value::from(byte_format.1);
+                Ok(input
-                    ActionStream::one(ReturnSuccess::value(
+                    .replace_data_at_column_path(&field, byte_value)
-                        input.replace_data_at_column_path(&field, byte_value).expect("Given that the existence check was already done, this shouldn't trigger never"),
+                    .expect(
-                    ))
+                    "Given that the existence check was already done, this shouldn't trigger never",
-                } else {
+                ))
-                    return Err(ShellError::labeled_error(
+            } else {
-                        "the data in this row is not of the type filesize",
+                Err(ShellError::labeled_error(
-                        "invalid datatype in row",
+                    "the data in this row is not of the type filesize",
-                        input.tag(),
+                    "invalid datatype in row",
-                    ));
+                    input.tag(),
-                }
+                ))
             }
-            Err(e) => ActionStream::one(Err(e)),
         }
-    })
+        Err(e) => Err(e),
+    }
 }
 
-fn filesize(raw_args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn filesize(raw_args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let (Arguments { field, format }, input) = raw_args.process()?;
+    let args = raw_args.evaluate_once()?;
+
+    let field: ColumnPath = args.req(0)?;
+    let format: Tagged<String> = args.req(1)?;
     let field = Arc::new(field);
 
-    Ok(input
+    Ok(args
+        .input
         .map(move |input| {
             let format = format.clone();
             let field = field.clone();
 
             match process_row(input, format, field) {
-                Ok(s) => s,
+                Ok(s) => Ok(s),
-                Err(e) => ActionStream::one(Err(e)),
+                Err(e) => Err(e),
             }
         })
         .flatten()
-        .to_action_stream())
+        .map(Ok)
+        .to_input_stream())
 }
 
 #[cfg(test)]

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

@@ -20,7 +20,7 @@ impl WholeStreamCommand for From {
 
     fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         Ok(OutputStream::one(
-            UntaggedValue::string(get_full_help(&From, &args.scope)).into_value(Tag::unknown()),
+            UntaggedValue::string(get_full_help(&From, args.scope())).into_value(Tag::unknown()),
         ))
     }
 }

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

@@ -35,7 +35,7 @@ fn convert_json_value_to_nu_value(v: &nu_json::Value, tag: impl Into<Tag>) -> Va
         nu_json::Value::Null => UntaggedValue::Primitive(Primitive::Nothing).into_value(&tag),
         nu_json::Value::Bool(b) => UntaggedValue::boolean(*b).into_value(&tag),
         nu_json::Value::F64(n) => UntaggedValue::decimal_from_float(*n, span).into_value(&tag),
-        nu_json::Value::U64(n) => UntaggedValue::int(*n).into_value(&tag),
+        nu_json::Value::U64(n) => UntaggedValue::big_int(*n).into_value(&tag),
         nu_json::Value::I64(n) => UntaggedValue::int(*n).into_value(&tag),
         nu_json::Value::String(s) => {
             UntaggedValue::Primitive(Primitive::String(String::from(s))).into_value(&tag)

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

@@ -228,8 +228,8 @@ pub fn get_column_from_row_error(
         } => {
             let primary_label = format!("There isn't a column named '{}'", &column);
 
-            if let Some(suggestions) = did_you_mean(&obj_source, column_path_tried.as_string()) {
+            did_you_mean(&obj_source, column_path_tried.as_string()).map(|suggestions| {
-                Some(ShellError::labeled_error_with_secondary(
+                ShellError::labeled_error_with_secondary(
                     "Unknown column",
                     primary_label,
                     column_path_tried.span,
@@ -239,10 +239,8 @@ pub fn get_column_from_row_error(
                         &obj_source.data_descriptors().join(", ")
                     ),
                     column_path_tried.span.since(path_members_span),
-                ))
+                )
-            } else {
+            })
-                None
-            }
         }
         PathMember {
             unspanned: UnspannedPathMember::Int(idx),

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

@@ -2,17 +2,13 @@ use crate::prelude::*;
 use crate::utils::suggestions::suggestions;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
+use nu_protocol::hir::ExternalRedirection;
 use nu_protocol::{Signature, SyntaxShape, UntaggedValue, Value};
 use nu_source::Tagged;
 use nu_value_ext::as_string;
 
 pub struct Command;
 
-#[derive(Deserialize)]
-pub struct Arguments {
-    grouper: Option<Value>,
-}
-
 impl WholeStreamCommand for Command {
     fn name(&self) -> &str {
         "group-by"
@@ -99,7 +95,7 @@ impl WholeStreamCommand for Command {
             Example {
                 description:
                     "use the block form to generate a grouping key when each row gets processed",
-                example: "echo [1 3 1 3 2 1 1] | group-by { = ($it - 1) mod 3 }",
+                example: "echo [1 3 1 3 2 1 1] | group-by { ($it - 1) mod 3 }",
                 result: Some(vec![UntaggedValue::row(indexmap! {
                     "0".to_string() => UntaggedValue::Table(vec![
                         UntaggedValue::int(1).into(),
@@ -130,9 +126,10 @@ enum Grouper {
 pub fn group_by(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let name = args.call_info.name_tag.clone();
     let context = Arc::new(EvaluationContext::from_args(&args));
-    let (Arguments { grouper }, input) = args.process()?;
+    let args = args.evaluate_once()?;
 
-    let values: Vec<Value> = input.collect();
+    let grouper = args.opt(0)?;
+    let values: Vec<Value> = args.input.collect();
     let mut keys: Vec<Result<String, ShellError>> = vec![];
     let mut group_strategy = Grouper::ByColumn(None);
 
@@ -148,7 +145,12 @@ pub fn group_by(args: CommandArgs) -> Result<OutputStream, ShellError> {
                 let run = block.clone();
                 let context = context.clone();
 
-                match crate::commands::each::process_row(run, context, value.clone()) {
+                match crate::commands::each::process_row(
+                    run,
+                    context,
+                    value.clone(),
+                    ExternalRedirection::Stdout,
+                ) {
                     Ok(mut s) => {
                         let collection: Vec<Value> = s.drain_vec();
 

crates/nu-command/src/commands/hash_/base64_.rs

@@ -2,21 +2,11 @@ use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
 use nu_protocol::ShellTypeName;
-use nu_protocol::{
+use nu_protocol::{ColumnPath, Primitive, Signature, SyntaxShape, UntaggedValue, Value};
-    ColumnPath, Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
-};
 use nu_source::{Tag, Tagged};
 
 use base64::{decode_config, encode_config};
 
-#[derive(Deserialize)]
-pub struct Arguments {
-    pub rest: Vec<ColumnPath>,
-    pub character_set: Option<Tagged<String>>,
-    pub encode: Tagged<bool>,
-    pub decode: Tagged<bool>,
-}
-
 #[derive(Clone)]
 pub struct Base64Config {
     pub character_set: String,
@@ -46,13 +36,13 @@ impl WholeStreamCommand for SubCommand {
                 Some('c'),
             )
             .switch(
-                "encode", 
+                "encode",
-                "encode the input as base64. This is the default behavior if not specified.", 
+                "encode the input as base64. This is the default behavior if not specified.",
                 Some('e')
             )
             .switch(
-                "decode", 
+                "decode",
-                "decode the input from base64", 
+                "decode the input from base64",
                 Some('d'))
             .rest(
                 SyntaxShape::ColumnPath,
@@ -64,7 +54,7 @@ impl WholeStreamCommand for SubCommand {
         "base64 encode or decode a value"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         operate(args)
     }
 
@@ -95,29 +85,25 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-fn operate(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn operate(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let name_tag = args.call_info.name_tag.clone();
+    let args = args.evaluate_once()?;
 
-    let (
+    let encode = args.has_flag("encode");
-        Arguments {
+    let decode = args.has_flag("decode");
-            encode,
+    let character_set: Option<Tagged<String>> = args.get_flag("character_set")?;
-            decode,
+    let column_paths: Vec<ColumnPath> = args.rest(0)?;
-            character_set,
-            rest,
-        },
-        input,
-    ) = args.process()?;
 
-    if encode.item && decode.item {
+    if encode && decode {
-        return Ok(ActionStream::one(Err(ShellError::labeled_error(
+        return Err(ShellError::labeled_error(
             "only one of --decode and --encode flags can be used",
             "conflicting flags",
             name_tag,
-        ))));
+        ));
     }
 
     // Default the action to be encoding if no flags are specified.
-    let action_type = if *decode.item() {
+    let action_type = if decode {
         ActionType::Decode
     } else {
         ActionType::Encode
@@ -134,12 +120,11 @@ fn operate(args: CommandArgs) -> Result<ActionStream, ShellError> {
         action_type,
     };
 
-    let column_paths: Vec<_> = rest;
+    Ok(args
-
+        .input
-    Ok(input
         .map(move |v| {
             if column_paths.is_empty() {
-                ReturnSuccess::value(action(&v, &encoding_config, v.tag())?)
+                action(&v, &encoding_config, v.tag())
             } else {
                 let mut ret = v;
 
@@ -151,10 +136,10 @@ fn operate(args: CommandArgs) -> Result<ActionStream, ShellError> {
                     )?;
                 }
 
-                ReturnSuccess::value(ret)
+                Ok(ret)
             }
         })
-        .to_action_stream())
+        .to_input_stream())
 }
 
 fn action(
@@ -182,7 +167,7 @@ fn action(
                 return Err(ShellError::labeled_error(
                     "value is not an accepted character set",
                     format!(
-                        "{} is not a valid character-set.\nPlease use `help hash base64` to see a list of valid character sets.", 
+                        "{} is not a valid character-set.\nPlease use `help hash base64` to see a list of valid character sets.",
                         &base64_config.character_set
                     ),
                     tag.into().span,

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

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, UntaggedValue};
+use nu_protocol::{Signature, SyntaxShape, UntaggedValue};
 
 pub struct Command;
 
@@ -21,10 +21,10 @@ impl WholeStreamCommand for Command {
         "Apply hash function."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
-        Ok(ActionStream::one(ReturnSuccess::value(
+        Ok(OutputStream::one(
-            UntaggedValue::string(get_full_help(&Command, &args.scope)).into_value(Tag::unknown()),
+            UntaggedValue::string(get_full_help(&Command, args.scope())).into_value(Tag::unknown()),
-        )))
+        ))
     }
 }
 

crates/nu-command/src/commands/hash_/md5_.rs

@@ -2,16 +2,9 @@ use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
 use nu_protocol::ShellTypeName;
-use nu_protocol::{
+use nu_protocol::{ColumnPath, Primitive, Signature, SyntaxShape, UntaggedValue, Value};
-    ColumnPath, Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
-};
 use nu_source::Tag;
 
-#[derive(Deserialize)]
-pub struct Arguments {
-    pub rest: Vec<ColumnPath>,
-}
-
 pub struct SubCommand;
 
 impl WholeStreamCommand for SubCommand {
@@ -30,7 +23,7 @@ impl WholeStreamCommand for SubCommand {
         "md5 encode a value"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         operate(args)
     }
 
@@ -56,15 +49,15 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-fn operate(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn operate(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let (Arguments { rest }, input) = args.process()?;
+    let args = args.evaluate_once()?;
+    let column_paths: Vec<ColumnPath> = args.rest(0)?;
 
-    let column_paths: Vec<_> = rest;
+    Ok(args
-
+        .input
-    Ok(input
         .map(move |v| {
             if column_paths.is_empty() {
-                ReturnSuccess::value(action(&v, v.tag())?)
+                action(&v, v.tag())
             } else {
                 let mut ret = v;
 
@@ -75,10 +68,10 @@ fn operate(args: CommandArgs) -> Result<ActionStream, ShellError> {
                     )?;
                 }
 
-                ReturnSuccess::value(ret)
+                Ok(ret)
             }
         })
-        .to_action_stream())
+        .to_input_stream())
 }
 
 fn action(input: &Value, tag: impl Into<Tag>) -> Result<Value, ShellError> {

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

@@ -38,7 +38,7 @@ impl WholeStreamCommand for Help {
 
 fn help(args: CommandArgs) -> Result<ActionStream, ShellError> {
     let name = args.call_info.name_tag.clone();
-    let scope = args.scope.clone();
+    let scope = args.scope().clone();
     let (HelpArgs { rest }, ..) = args.process()?;
 
     if !rest.is_empty() {

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

@@ -76,10 +76,10 @@ pub fn histogram(args: CommandArgs) -> Result<ActionStream, ShellError> {
     };
 
     let column_grouper = if !columns.is_empty() {
-        match columns.remove(0).split_last() {
+        columns
-            Some((key, _)) => Some(key.as_string().tagged(&name)),
+            .remove(0)
-            None => None,
+            .split_last()
-        }
+            .map(|(key, _)| key.as_string().tagged(&name))
     } else {
         None
     };
@@ -160,7 +160,7 @@ pub fn histogram(args: CommandArgs) -> Result<ActionStream, ShellError> {
                 "{}%",
                 // Some(2) < the number of digits
                 // true < group the digits
-                crate::commands::str_::from::action(&percentage, &name, Some(2), true)?
+                crate::commands::into::string::action(&percentage, &name, Some(2), true)?
                     .as_string()?
             );
             fact.insert_untagged("percentage", UntaggedValue::string(fmt_percentage));

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

@@ -59,6 +59,7 @@ impl WholeStreamCommand for If {
 }
 fn if_command(raw_args: CommandArgs) -> Result<OutputStream, ShellError> {
     let tag = raw_args.call_info.name_tag.clone();
+    let external_redirection = raw_args.call_info.args.external_redirection;
     let context = Arc::new(EvaluationContext::from_args(&raw_args));
 
     let args = raw_args.evaluate_once()?;
@@ -105,9 +106,9 @@ fn if_command(raw_args: CommandArgs) -> Result<OutputStream, ShellError> {
         Ok(condition) => match condition.as_bool() {
             Ok(b) => {
                 let result = if b {
-                    run_block(&then_case.block, &*context, input)
+                    run_block(&then_case.block, &*context, input, external_redirection)
                 } else {
-                    run_block(&else_case.block, &*context, input)
+                    run_block(&else_case.block, &*context, input, external_redirection)
                 };
                 context.scope.exit_scope();
 

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

@@ -2,6 +2,7 @@ use crate::prelude::*;
 use nu_engine::run_block;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
+use nu_protocol::hir::ExternalRedirection;
 use nu_protocol::{
     ColumnPath, Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
 };
@@ -50,7 +51,7 @@ impl WholeStreamCommand for Command {
             .into()]),
         },Example {
             description: "Use in block form for more involved insertion logic",
-            example: "echo [[author, lucky_number]; ['Yehuda', 4]] | insert success { = $it.lucky_number * 10 }",
+            example: "echo [[author, lucky_number]; ['Yehuda', 4]] | insert success { $it.lucky_number * 10 }",
             result: Some(vec![UntaggedValue::row(indexmap! {
                     "author".to_string() => Value::from("Yehuda"),
                     "lucky_number".to_string() => UntaggedValue::int(4).into(),
@@ -79,9 +80,16 @@ fn process_row(
 
             context.scope.enter_scope();
             context.scope.add_vars(&block.captured.entries);
-            context.scope.add_var("$it", input.clone());
+            if let Some((arg, _)) = block.block.params.positional.first() {
+                context.scope.add_var(arg.name(), input.clone());
+            }
 
-            let result = run_block(&block.block, &*context, input_stream);
+            let result = run_block(
+                &block.block,
+                &*context,
+                input_stream,
+                ExternalRedirection::Stdout,
+            );
 
             context.scope.exit_scope();
 

crates/nu-command/src/commands/into/binary.rs

@@ -0,0 +1,270 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+use nu_errors::ShellError;
+use nu_protocol::{ColumnPath, Primitive, Signature, SyntaxShape, UntaggedValue, Value};
+use num_bigint::{BigInt, ToBigInt};
+
+pub struct SubCommand;
+
+impl WholeStreamCommand for SubCommand {
+    fn name(&self) -> &str {
+        "into binary"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("into binary")
+            .rest(
+                SyntaxShape::ColumnPath,
+                "column paths to convert to binary (for table input)",
+            )
+            .named(
+                "skip",
+                SyntaxShape::Int,
+                "skip x number of bytes",
+                Some('s'),
+            )
+            .named(
+                "bytes",
+                SyntaxShape::Int,
+                "show y number of bytes",
+                Some('b'),
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "Convert value to a binary primitive"
+    }
+
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        into_binary(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "convert string to a nushell binary primitive",
+                example:
+                    "echo 'This is a string that is exactly 52 characters long.' | into binary",
+                result: Some(vec![UntaggedValue::binary(
+                    "This is a string that is exactly 52 characters long."
+                        .to_string()
+                        .as_bytes()
+                        .to_vec(),
+                )
+                .into()]),
+            },
+            Example {
+                description: "convert string to a nushell binary primitive",
+                example:
+                    "echo 'This is a string that is exactly 52 characters long.' | into binary --skip 10",
+                result: Some(vec![UntaggedValue::binary(
+                    "string that is exactly 52 characters long."
+                        .to_string()
+                        .as_bytes()
+                        .to_vec(),
+                )
+                .into()]),
+            },
+            Example {
+                description: "convert string to a nushell binary primitive",
+                example:
+                    "echo 'This is a string that is exactly 52 characters long.' | into binary --skip 10 --bytes 10",
+                result: Some(vec![UntaggedValue::binary(
+                    "string tha"
+                        .to_string()
+                        .as_bytes()
+                        .to_vec(),
+                )
+                .into()]),
+            },
+            Example {
+                description: "convert a number to a nushell binary primitive",
+                example: "echo 1 | into binary",
+                result: Some(vec![
+                    UntaggedValue::binary(i64::from(1).to_le_bytes().to_vec()).into()
+                ]),
+            },
+            Example {
+                description: "convert a boolean to a nushell binary primitive",
+                example: "echo $true | into binary",
+                result: Some(vec![
+                    UntaggedValue::binary(i64::from(1).to_le_bytes().to_vec()).into()
+                ]),
+            },
+            Example {
+                description: "convert a filesize to a nushell binary primitive",
+                example: "ls | where name == LICENSE | get size | into binary",
+                result: None,
+            },
+            Example {
+                description: "convert a filepath to a nushell binary primitive",
+                example: "ls | where name == LICENSE | get name | path expand | into binary",
+                result: None,
+            },
+            Example {
+                description: "convert a decimal to a nushell binary primitive",
+                example: "echo 1.234 | into binary",
+                result: Some(vec![
+                    UntaggedValue::binary(BigInt::from(1).to_bytes_le().1).into()
+                ]),
+            },
+        ]
+    }
+}
+
+fn into_binary(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let args = args.evaluate_once()?;
+    let skip: Option<Value> = args.get_flag("skip")?;
+    let bytes: Option<Value> = args.get_flag("bytes")?;
+    let column_paths: Vec<ColumnPath> = args.rest(0)?;
+
+    Ok(args
+        .input
+        .map(move |v| {
+            if column_paths.is_empty() {
+                action(&v, v.tag(), &skip, &bytes)
+            } else {
+                let mut ret = v;
+                for path in &column_paths {
+                    let skip_clone = skip.clone();
+                    let bytes_clone = bytes.clone();
+                    ret = ret.swap_data_by_column_path(
+                        path,
+                        Box::new(move |old| action(old, old.tag(), &skip_clone, &bytes_clone)),
+                    )?;
+                }
+
+                Ok(ret)
+            }
+        })
+        .to_input_stream())
+}
+
+fn int_to_endian(n: i64) -> Vec<u8> {
+    if cfg!(target_endian = "little") {
+        // eprintln!("Little Endian");
+        n.to_le_bytes().to_vec()
+    } else {
+        // eprintln!("Big Endian");
+        n.to_be_bytes().to_vec()
+    }
+}
+
+fn bigint_to_endian(n: &BigInt) -> Vec<u8> {
+    if cfg!(target_endian = "little") {
+        // eprintln!("Little Endian");
+        n.to_bytes_le().1
+    } else {
+        // eprintln!("Big Endian");
+        n.to_bytes_be().1
+    }
+}
+
+pub fn action(
+    input: &Value,
+    tag: impl Into<Tag>,
+    skip: &Option<Value>,
+    bytes: &Option<Value>,
+) -> Result<Value, ShellError> {
+    let tag = tag.into();
+    let skip_bytes = match skip {
+        Some(s) => s.as_usize().unwrap_or(0),
+        None => 0usize,
+    };
+
+    let num_bytes = match bytes {
+        Some(b) => b.as_usize().unwrap_or(0),
+        None => 0usize,
+    };
+
+    match &input.value {
+        UntaggedValue::Primitive(prim) => Ok(UntaggedValue::binary(match prim {
+            Primitive::Binary(b) => {
+                if num_bytes == 0usize {
+                    b.to_vec().into_iter().skip(skip_bytes).collect()
+                } else {
+                    b.to_vec()
+                        .into_iter()
+                        .skip(skip_bytes)
+                        .take(num_bytes)
+                        .collect()
+                }
+            }
+            Primitive::Int(n_ref) => int_to_endian(*n_ref),
+            Primitive::BigInt(n_ref) => bigint_to_endian(n_ref),
+            Primitive::Decimal(dec) => match dec.to_bigint() {
+                Some(n) => bigint_to_endian(&n),
+                None => {
+                    return Err(ShellError::unimplemented(
+                        "failed to convert decimal to int",
+                    ));
+                }
+            },
+            Primitive::Filesize(a_filesize) => match a_filesize.to_bigint() {
+                Some(n) => bigint_to_endian(&n),
+                None => {
+                    return Err(ShellError::unimplemented(
+                        "failed to convert filesize to bigint",
+                    ));
+                }
+            },
+            Primitive::String(a_string) => {
+                // a_string.as_bytes().to_vec()
+                if num_bytes == 0usize {
+                    a_string
+                        .as_bytes()
+                        .to_vec()
+                        .into_iter()
+                        .skip(skip_bytes)
+                        .collect()
+                } else {
+                    a_string
+                        .as_bytes()
+                        .to_vec()
+                        .into_iter()
+                        .skip(skip_bytes)
+                        .take(num_bytes)
+                        .collect()
+                }
+            }
+            Primitive::Boolean(a_bool) => match a_bool {
+                false => int_to_endian(0),
+                true => int_to_endian(1),
+            },
+            Primitive::Date(a_date) => a_date.format("%c").to_string().as_bytes().to_vec(),
+            Primitive::FilePath(a_filepath) => a_filepath
+                .as_path()
+                .display()
+                .to_string()
+                .as_bytes()
+                .to_vec(),
+            _ => {
+                return Err(ShellError::unimplemented(
+                    "'into binary' for non-numeric primitives",
+                ))
+            }
+        })
+        .into_value(&tag)),
+        UntaggedValue::Row(_) => Err(ShellError::labeled_error(
+            "specify column name to use, with 'into binary COLUMN'",
+            "found table",
+            tag,
+        )),
+        _ => Err(ShellError::unimplemented(
+            "'into binary' for unsupported type",
+        )),
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::ShellError;
+    use super::SubCommand;
+
+    #[test]
+    fn examples_work_as_expected() -> Result<(), ShellError> {
+        use crate::examples::test as test_examples;
+
+        test_examples(SubCommand {})
+    }
+}

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

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, Signature, UntaggedValue};
+use nu_protocol::{Signature, UntaggedValue};
 
 pub struct Command;
 
@@ -18,10 +18,10 @@ impl WholeStreamCommand for Command {
         "Apply into function."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
-        Ok(ActionStream::one(ReturnSuccess::value(
+        Ok(OutputStream::one(
-            UntaggedValue::string(get_full_help(&Command, &args.scope)).into_value(Tag::unknown()),
+            UntaggedValue::string(get_full_help(&Command, args.scope())).into_value(Tag::unknown()),
-        )))
+        ))
     }
 }
 

crates/nu-command/src/commands/into/int.rs

@@ -1,18 +1,11 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{
+use nu_protocol::{ColumnPath, Primitive, Signature, SyntaxShape, UntaggedValue, Value};
-    ColumnPath, Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
+use num_bigint::ToBigInt;
-};
-use num_bigint::{BigInt, ToBigInt};
 
 pub struct SubCommand;
 
-#[derive(Deserialize)]
-pub struct Arguments {
-    pub rest: Vec<ColumnPath>,
-}
-
 impl WholeStreamCommand for SubCommand {
     fn name(&self) -> &str {
         "into int"
@@ -29,7 +22,7 @@ impl WholeStreamCommand for SubCommand {
         "Convert value to integer"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         into_int(args)
     }
 
@@ -85,13 +78,15 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-fn into_int(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn into_int(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let (Arguments { rest: column_paths }, input) = args.process()?;
+    let args = args.evaluate_once()?;
+    let column_paths: Vec<ColumnPath> = args.rest(0)?;
 
-    Ok(input
+    Ok(args
+        .input
         .map(move |v| {
             if column_paths.is_empty() {
-                ReturnSuccess::value(action(&v, v.tag())?)
+                action(&v, v.tag())
             } else {
                 let mut ret = v;
                 for path in &column_paths {
@@ -101,10 +96,10 @@ fn into_int(args: CommandArgs) -> Result<ActionStream, ShellError> {
                     )?;
                 }
 
-                ReturnSuccess::value(ret)
+                Ok(ret)
             }
         })
-        .to_action_stream())
+        .to_input_stream())
 }
 
 pub fn action(input: &Value, tag: impl Into<Tag>) -> Result<Value, ShellError> {
@@ -118,20 +113,34 @@ pub fn action(input: &Value, tag: impl Into<Tag>) -> Result<Value, ShellError> {
                 }
             },
             Primitive::Decimal(dec) => match dec.to_bigint() {
-                Some(n) => n,
+                Some(n) => match n.to_i64() {
+                    Some(i) => i,
+                    None => {
+                        return Err(ShellError::unimplemented(
+                            "failed to convert decimal to int",
+                        ));
+                    }
+                },
                 None => {
                     return Err(ShellError::unimplemented(
                         "failed to convert decimal to int",
                     ));
                 }
             },
-            Primitive::Int(n_ref) => n_ref.to_owned(),
+            Primitive::Int(n_ref) => *n_ref,
             Primitive::Boolean(a_bool) => match a_bool {
-                false => BigInt::from(0),
+                false => 0,
-                true => BigInt::from(1),
+                true => 1,
             },
             Primitive::Filesize(a_filesize) => match a_filesize.to_bigint() {
-                Some(n) => n,
+                Some(n) => match n.to_i64() {
+                    Some(i) => i,
+                    None => {
+                        return Err(ShellError::unimplemented(
+                            "failed to convert filesize to bigint",
+                        ));
+                    }
+                },
                 None => {
                     return Err(ShellError::unimplemented(
                         "failed to convert filesize to bigint",
@@ -154,13 +163,17 @@ pub fn action(input: &Value, tag: impl Into<Tag>) -> Result<Value, ShellError> {
     }
 }
 
-fn int_from_string(a_string: &str, tag: &Tag) -> Result<BigInt, ShellError> {
+fn int_from_string(a_string: &str, tag: &Tag) -> Result<i64, ShellError> {
-    match a_string.parse::<BigInt>() {
+    match a_string.parse::<i64>() {
         Ok(n) => Ok(n),
         Err(_) => match a_string.parse::<f64>() {
-            Ok(res_float) => match res_float.to_bigint() {
+            Ok(f) => match f.to_i64() {
-                Some(n) => Ok(n),
+                Some(i) => Ok(i),
-                None => Err(ShellError::unimplemented("failed to convert f64 to int")),
+                None => Err(ShellError::labeled_error(
+                    "Could not convert string value to int",
+                    "original value",
+                    tag.clone(),
+                )),
             },
             Err(_) => Err(ShellError::labeled_error(
                 "Could not convert string value to int",

crates/nu-command/src/commands/into/mod.rs

@@ -1,5 +1,9 @@
+mod binary;
 mod command;
 mod int;
+pub mod string;
 
+pub use binary::SubCommand as IntoBinary;
 pub use command::Command as Into;
 pub use int::SubCommand as IntoInt;
+pub use string::SubCommand as IntoString;

crates/nu-command/src/commands/into/string.rs

@@ -1,9 +1,7 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{
+use nu_protocol::{ColumnPath, Primitive, Signature, SyntaxShape, UntaggedValue, Value};
-    ColumnPath, Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
-};
 use nu_source::Tagged;
 use num_bigint::{BigInt, BigUint, ToBigInt};
 // TODO num_format::SystemLocale once platform-specific dependencies are stable (see Cargo.toml)
@@ -14,22 +12,16 @@ use std::iter;
 
 pub struct SubCommand;
 
-struct Arguments {
-    decimals: Option<Tagged<u64>>,
-    group_digits: bool,
-    column_paths: Vec<ColumnPath>,
-}
-
 impl WholeStreamCommand for SubCommand {
     fn name(&self) -> &str {
-        "str from"
+        "into string"
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("str from")
+        Signature::build("into string")
             .rest(
                 SyntaxShape::ColumnPath,
-                "optionally convert to string by column paths",
+                "column paths to convert to string (for table input)",
             )
             .named(
                 "decimals",
@@ -40,66 +32,83 @@ impl WholeStreamCommand for SubCommand {
     }
 
     fn usage(&self) -> &str {
-        "Converts numeric types to strings. Trims trailing zeros unless decimals parameter is specified."
+        "Convert value to string"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
-        operate(args)
+        into_string(args)
     }
 
     fn examples(&self) -> Vec<Example> {
         vec![
             Example {
-                description: "round to nearest integer",
+                description: "convert decimal to string and round to nearest integer",
-                example: "echo 1.7 | str from -d 0",
+                example: "echo 1.7 | into string -d 0",
                 result: Some(vec![UntaggedValue::string("2").into_untagged_value()]),
             },
-            /*
-            FIXME: this isn't currently supported because of num_format being out of date. Once it's updated, re-enable this
             Example {
-                description: "format large number with localized digit grouping",
+                description: "convert decimal to string",
-                example: "= 1000000.2 | str from -g",
+                example: "echo 4.3 | into string",
-                result: Some(vec![
+                result: Some(vec![UntaggedValue::string("4.3").into_untagged_value()]),
-                    UntaggedValue::string("1,000,000.2").into_untagged_value()
+            },
-                ]),
+            Example {
+                description: "convert string to string",
+                example: "echo '1234' | into string",
+                result: Some(vec![UntaggedValue::string("1234").into_untagged_value()]),
+            },
+            Example {
+                description: "convert boolean to string",
+                example: "echo $true | into string",
+                result: Some(vec![UntaggedValue::string("true").into_untagged_value()]),
+            },
+            Example {
+                description: "convert date to string",
+                example: "date now | into string",
+                result: None,
+            },
+            Example {
+                description: "convert filepath to string",
+                example: "ls Cargo.toml | get name | into string",
+                result: None,
+            },
+            Example {
+                description: "convert filesize to string",
+                example: "ls Cargo.toml | get size | into string",
+                result: None,
             },
-            */
         ]
     }
 }
 
-fn operate(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn into_string(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let (options, input) = args.extract(|params| {
+    let args = args.evaluate_once()?;
-        Ok(Arguments {
-            decimals: params.get_flag("decimals")?,
-            group_digits: false,
-            column_paths: params.rest_args()?,
-        })
-    })?;
 
-    let digits = options.decimals.as_ref().map(|tagged| tagged.item);
+    let decimals: Option<Tagged<u64>> = args.get_flag("decimals")?;
-    let group_digits = options.group_digits;
+    let column_paths: Vec<ColumnPath> = args.rest(0)?;
 
-    Ok(input
+    let digits = decimals.as_ref().map(|tagged| tagged.item);
+    let group_digits = false;
+
+    Ok(args
+        .input
         .map(move |v| {
-            if options.column_paths.is_empty() {
+            if column_paths.is_empty() {
-                ReturnSuccess::value(action(&v, v.tag(), digits, group_digits)?)
+                action(&v, v.tag(), digits, group_digits)
             } else {
                 let mut ret = v;
-                for path in &options.column_paths {
+                for path in &column_paths {
                     ret = ret.swap_data_by_column_path(
                         path,
                         Box::new(move |old| action(old, old.tag(), digits, group_digits)),
                     )?;
                 }
 
-                ReturnSuccess::value(ret)
+                Ok(ret)
             }
         })
-        .to_action_stream())
+        .to_input_stream())
 }
 
-// TODO If you're using the with-system-locale feature and you're on Windows, Clang 3.9 or higher is also required.
 pub fn action(
     input: &Value,
     tag: impl Into<Tag>,
@@ -109,6 +118,13 @@ pub fn action(
     match &input.value {
         UntaggedValue::Primitive(prim) => Ok(UntaggedValue::string(match prim {
             Primitive::Int(int) => {
+                if group_digits {
+                    format_int(*int) // int.to_formatted_string(*locale)
+                } else {
+                    int.to_string()
+                }
+            }
+            Primitive::BigInt(int) => {
                 if group_digits {
                     format_bigint(int) // int.to_formatted_string(*locale)
                 } else {
@@ -121,27 +137,45 @@ pub fn action(
             Primitive::Date(a_date) => a_date.format("%c").to_string(),
             Primitive::FilePath(a_filepath) => a_filepath.as_path().display().to_string(),
             Primitive::Filesize(a_filesize) => {
-                let byte_string = InlineShape::format_bytes(a_filesize, None);
+                let byte_string = InlineShape::format_bytes(*a_filesize, None);
                 byte_string.1
             }
+            Primitive::Nothing => "nothing".to_string(),
             _ => {
-                return Err(ShellError::unimplemented(
+                return Err(ShellError::unimplemented(&format!(
-                    "str from for non-numeric primitives",
+                    "into string for primitive: {:?}",
-                ))
+                    prim
+                )))
             }
         })
         .into_value(tag)),
         UntaggedValue::Row(_) => Err(ShellError::labeled_error(
-            "specify column to use 'str from'",
+            "specify column to use 'into string'",
             "found table",
             input.tag.clone(),
         )),
-        _ => Err(ShellError::unimplemented(
+        UntaggedValue::Table(_) => Err(ShellError::unimplemented("into string for table")),
-            "str from for non-primitive, non-table types",
+        _ => Err(ShellError::unimplemented("into string for non-primitive")),
-        )),
     }
 }
 
+fn format_int(int: i64) -> String {
+    format!("{}", int)
+
+    // TODO once platform-specific dependencies are stable (see Cargo.toml)
+    // #[cfg(windows)]
+    // {
+    //     int.to_formatted_string(&Locale::en)
+    // }
+    // #[cfg(not(windows))]
+    // {
+    //     match SystemLocale::default() {
+    //         Ok(locale) => int.to_formatted_string(&locale),
+    //         Err(_) => int.to_formatted_string(&Locale::en),
+    //     }
+    // }
+}
+
 fn format_bigint(int: &BigInt) -> String {
     format!("{}", int)
 

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

@@ -6,11 +6,6 @@ use nu_source::Tagged;
 
 pub struct Command;
 
-#[derive(Deserialize)]
-pub struct Arguments {
-    rows: Option<Tagged<usize>>,
-}
-
 impl WholeStreamCommand for Command {
     fn name(&self) -> &str {
         "keep"
@@ -28,7 +23,7 @@ impl WholeStreamCommand for Command {
         "Keep the number of rows only."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         keep(args)
     }
 
@@ -53,15 +48,17 @@ impl WholeStreamCommand for Command {
     }
 }
 
-fn keep(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn keep(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let (Arguments { rows }, input) = args.process()?;
+    let args = args.evaluate_once()?;
+    let rows: Option<Tagged<usize>> = args.opt(0)?;
+
     let rows_desired = if let Some(quantity) = rows {
         *quantity
     } else {
         1
     };
 
-    Ok(input.take(rows_desired).to_action_stream())
+    Ok(args.input.take(rows_desired).to_output_stream())
 }
 
 #[cfg(test)]

crates/nu-command/src/commands/keep/until.rs

@@ -1,10 +1,12 @@
 use crate::prelude::*;
-use log::trace;
 use nu_engine::evaluate_baseline_expr;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
 use nu_parser::ParserScope;
-use nu_protocol::{hir::ClassifiedCommand, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_protocol::{
+    hir::{CapturedBlock, ClassifiedCommand},
+    Signature, SyntaxShape,
+};
 
 pub struct SubCommand;
 
@@ -27,54 +29,40 @@ impl WholeStreamCommand for SubCommand {
         "Keeps rows until the condition matches."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         let ctx = Arc::new(EvaluationContext::from_args(&args));
+        let tag = args.call_info.name_tag.clone();
 
         let call_info = args.evaluate_once()?;
 
-        let block = call_info.args.expect_nth(0)?.clone();
+        let block: CapturedBlock = call_info.req(0)?;
-
+        let condition = {
-        let (condition, captured) = match block {
+            if block.block.block.len() != 1 {
-            Value {
+                return Err(ShellError::labeled_error(
-                value: UntaggedValue::Block(captured_block),
+                    "Expected a condition",
-                tag,
+                    "expected a condition",
-            } => {
+                    tag,
-                if captured_block.block.block.len() != 1 {
+                ));
-                    return Err(ShellError::labeled_error(
+            }
-                        "Expected a condition",
+            match block.block.block[0].pipelines.get(0) {
-                        "expected a condition",
+                Some(item) => match item.list.get(0) {
-                        tag,
+                    Some(ClassifiedCommand::Expr(expr)) => expr.clone(),
-                    ));
+                    _ => {
-                }
-                match captured_block.block.block[0].pipelines.get(0) {
-                    Some(item) => match item.list.get(0) {
-                        Some(ClassifiedCommand::Expr(expr)) => {
-                            (Arc::new(expr.clone()), captured_block.captured.clone())
-                        }
-                        _ => {
-                            return Err(ShellError::labeled_error(
-                                "Expected a condition",
-                                "expected a condition",
-                                tag,
-                            ));
-                        }
-                    },
-                    None => {
                         return Err(ShellError::labeled_error(
                             "Expected a condition",
                             "expected a condition",
                             tag,
                         ));
                     }
+                },
+                None => {
+                    return Err(ShellError::labeled_error(
+                        "Expected a condition",
+                        "expected a condition",
+                        tag,
+                    ));
                 }
             }
-            Value { tag, .. } => {
-                return Err(ShellError::labeled_error(
-                    "Expected a condition",
-                    "expected a condition",
-                    tag,
-                ));
-            }
         };
 
         Ok(call_info
@@ -83,17 +71,17 @@ impl WholeStreamCommand for SubCommand {
                 let condition = condition.clone();
                 let ctx = ctx.clone();
                 ctx.scope.enter_scope();
-                ctx.scope.add_vars(&captured.entries);
+                ctx.scope.add_vars(&block.captured.entries);
-                ctx.scope.add_var("$it", item.clone());
+                if let Some((arg, _)) = block.block.params.positional.first() {
-                trace!("ITEM = {:?}", item);
+                    ctx.scope.add_var(arg.name(), item.clone());
+                }
 
                 let result = evaluate_baseline_expr(&*condition, &*ctx);
                 ctx.scope.exit_scope();
-                trace!("RESULT = {:?}", result);
 
                 !matches!(result, Ok(ref v) if v.is_true())
             })
-            .to_action_stream())
+            .to_output_stream())
     }
 }
 

crates/nu-command/src/commands/keep/while_.rs

@@ -3,7 +3,10 @@ use log::trace;
 use nu_engine::evaluate_baseline_expr;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{hir::ClassifiedCommand, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_protocol::{
+    hir::{CapturedBlock, ClassifiedCommand},
+    Signature, SyntaxShape,
+};
 
 pub struct SubCommand;
 
@@ -26,53 +29,39 @@ impl WholeStreamCommand for SubCommand {
         "Keeps rows while the condition matches."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         let ctx = Arc::new(EvaluationContext::from_args(&args));
+        let tag = args.call_info.name_tag.clone();
         let call_info = args.evaluate_once()?;
 
-        let block = call_info.args.expect_nth(0)?.clone();
+        let block: CapturedBlock = call_info.req(0)?;
-
+        let condition = {
-        let (condition, captured) = match block {
+            if block.block.block.len() != 1 {
-            Value {
+                return Err(ShellError::labeled_error(
-                value: UntaggedValue::Block(captured_block),
+                    "Expected a condition",
-                tag,
+                    "expected a condition",
-            } => {
+                    tag,
-                if captured_block.block.block.len() != 1 {
+                ));
-                    return Err(ShellError::labeled_error(
+            }
-                        "Expected a condition",
+            match block.block.block[0].pipelines.get(0) {
-                        "expected a condition",
+                Some(item) => match item.list.get(0) {
-                        tag,
+                    Some(ClassifiedCommand::Expr(expr)) => expr.clone(),
-                    ));
+                    _ => {
-                }
-                match captured_block.block.block[0].pipelines.get(0) {
-                    Some(item) => match item.list.get(0) {
-                        Some(ClassifiedCommand::Expr(expr)) => {
-                            (Arc::new(expr.clone()), captured_block.captured.clone())
-                        }
-                        _ => {
-                            return Err(ShellError::labeled_error(
-                                "Expected a condition",
-                                "expected a condition",
-                                tag,
-                            ));
-                        }
-                    },
-                    None => {
                         return Err(ShellError::labeled_error(
                             "Expected a condition",
                             "expected a condition",
                             tag,
                         ));
                     }
+                },
+                None => {
+                    return Err(ShellError::labeled_error(
+                        "Expected a condition",
+                        "expected a condition",
+                        tag,
+                    ));
                 }
             }
-            Value { tag, .. } => {
-                return Err(ShellError::labeled_error(
-                    "Expected a condition",
-                    "expected a condition",
-                    tag,
-                ));
-            }
         };
 
         Ok(call_info
@@ -82,8 +71,10 @@ impl WholeStreamCommand for SubCommand {
                 let ctx = ctx.clone();
 
                 ctx.scope.enter_scope();
-                ctx.scope.add_var("$it", item.clone());
+                ctx.scope.add_vars(&block.captured.entries);
-                ctx.scope.add_vars(&captured.entries);
+                if let Some((arg, _)) = block.block.params.positional.first() {
+                    ctx.scope.add_var(arg.name(), item.clone());
+                }
                 trace!("ITEM = {:?}", item);
 
                 let result = evaluate_baseline_expr(&*condition, &*ctx);
@@ -92,7 +83,7 @@ impl WholeStreamCommand for SubCommand {
 
                 matches!(result, Ok(ref v) if v.is_true())
             })
-            .to_action_stream())
+            .to_output_stream())
     }
 }
 

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

@@ -1,16 +1,10 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{Signature, SyntaxShape, UntaggedValue, Value};
+use nu_protocol::{Signature, SyntaxShape, UntaggedValue};
-use nu_source::Tagged;
 
 pub struct Last;
 
-#[derive(Deserialize)]
-pub struct LastArgs {
-    rows: Option<Tagged<u64>>,
-}
-
 impl WholeStreamCommand for Last {
     fn name(&self) -> &str {
         "last"
@@ -28,7 +22,7 @@ impl WholeStreamCommand for Last {
         "Show only the last number of rows."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         last(args)
     }
 
@@ -37,7 +31,7 @@ impl WholeStreamCommand for Last {
             Example {
                 description: "Get the last row",
                 example: "echo [1 2 3] | last",
-                result: Some(vec![Value::from(UntaggedValue::from(BigInt::from(3)))]),
+                result: Some(vec![UntaggedValue::int(3).into()]),
             },
             Example {
                 description: "Get the last three rows",
@@ -52,12 +46,13 @@ impl WholeStreamCommand for Last {
     }
 }
 
-fn last(args: CommandArgs) -> Result<ActionStream, ShellError> {
+fn last(args: CommandArgs) -> Result<OutputStream, ShellError> {
-    let (LastArgs { rows }, input) = args.process()?;
+    let args = args.evaluate_once()?;
-    let v: Vec<_> = input.into_vec();
+    let rows = args.nth(0).cloned();
+    let v: Vec<_> = args.input.into_vec();
 
     let end_rows_desired = if let Some(quantity) = rows {
-        *quantity as usize
+        quantity.as_usize()?
     } else {
         1
     };
@@ -70,7 +65,7 @@ fn last(args: CommandArgs) -> Result<ActionStream, ShellError> {
 
     let iter = v.into_iter().skip(beginning_rows_to_skip);
 
-    Ok((iter).to_action_stream())
+    Ok(OutputStream::from_stream(iter))
 }
 
 #[cfg(test)]

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

@@ -94,7 +94,7 @@ impl Iterator for CountIterator {
             input.count()
         };
 
-        Some(UntaggedValue::int(length).into_value(self.tag.clone()))
+        Some(UntaggedValue::int(length as i64).into_value(self.tag.clone()))
     }
 }
 

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

@@ -1,9 +1,11 @@
 use crate::prelude::*;
-use nu_engine::{evaluate_baseline_expr, WholeStreamCommand};
+use nu_engine::{evaluate_baseline_expr, FromValue, WholeStreamCommand};
 
 use nu_errors::ShellError;
-use nu_protocol::{hir::CapturedBlock, hir::ClassifiedCommand, Signature, SyntaxShape};
+use nu_protocol::{
-use nu_source::Tagged;
+    hir::{CapturedBlock, ClassifiedCommand},
+    Signature, SyntaxShape, UntaggedValue,
+};
 
 pub struct Let;
 
@@ -32,20 +34,41 @@ impl WholeStreamCommand for Let {
     }
 
     fn examples(&self) -> Vec<Example> {
-        vec![]
+        vec![
+            Example {
+                description: "Assign a simple value to a variable",
+                example: "let x = 3",
+                result: Some(vec![]),
+            },
+            Example {
+                description: "Assign the result of an expression to a variable",
+                example: "let result = (3 + 7); echo $result",
+                result: Some(vec![UntaggedValue::int(1).into()]),
+            },
+            Example {
+                description: "Create a variable using the full name",
+                example: "let $three = 3",
+                result: Some(vec![]),
+            },
+        ]
     }
 }
 
 pub fn letcmd(args: CommandArgs) -> Result<ActionStream, ShellError> {
-    let tag = args.call_info.name_tag.clone();
     let ctx = EvaluationContext::from_args(&args);
-    let args = args.evaluate_once()?;
+    let positional = args
+        .call_info
+        .args
+        .positional
+        .expect("Internal error: type checker should require args");
 
-    //let (LetArgs { name, rhs, .. }, _) = args.process()?;
+    let var_name = positional[0].var_name()?;
-    let name: Tagged<String> = args.req(0)?;
+    let rhs_raw = evaluate_baseline_expr(&positional[2], &ctx)?;
-    let rhs: CapturedBlock = args.req(2)?;
+    let tag: Tag = positional[2].span.into();
 
-    let (expr, captured) = {
+    let rhs: CapturedBlock = FromValue::from_value(&rhs_raw)?;
+
+    let (expr, _) = {
         if rhs.block.block.len() != 1 {
             return Err(ShellError::labeled_error(
                 "Expected a value",
@@ -75,24 +98,15 @@ pub fn letcmd(args: CommandArgs) -> Result<ActionStream, ShellError> {
     };
 
     ctx.scope.enter_scope();
-    ctx.scope.add_vars(&captured.entries);
-
     let value = evaluate_baseline_expr(&expr, &ctx);
-
     ctx.scope.exit_scope();
 
     let value = value?;
 
-    let name = if name.item.starts_with('$') {
-        name.item
-    } else {
-        format!("${}", name.item)
-    };
-
     // Note: this is a special case for setting the context from a command
     // In this case, if we don't set it now, we'll lose the scope that this
     // variable should be set into.
-    ctx.scope.add_var(name, value);
+    ctx.scope.add_var(var_name, value);
 
     Ok(ActionStream::empty())
 }

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

@@ -0,0 +1,95 @@
+use crate::prelude::*;
+use nu_engine::WholeStreamCommand;
+
+use nu_errors::ShellError;
+use nu_protocol::{Signature, SyntaxShape, Value};
+
+pub struct LoadEnv;
+
+impl WholeStreamCommand for LoadEnv {
+    fn name(&self) -> &str {
+        "load-env"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("load-env").optional(
+            "environ",
+            SyntaxShape::Any,
+            "Optional environment table to load in. If not provided, will use the table provided on the input stream",
+        )
+    }
+
+    fn usage(&self) -> &str {
+        "Set environment variables using a table stream"
+    }
+
+    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+        load_env(args)
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Load variables from an input stream",
+                example: r#"echo [[name, value]; ["NAME", "JT"] ["AGE", "UNKNOWN"]] | load-env; echo $nu.env.NAME"#,
+                result: Some(vec![Value::from("JT")]),
+            },
+            Example {
+                description: "Load variables from an argument",
+                example: r#"load-env [[name, value]; ["NAME", "JT"] ["AGE", "UNKNOWN"]]; echo $nu.env.NAME"#,
+                result: Some(vec![Value::from("JT")]),
+            },
+            Example {
+                description: "Load variables from an argument and an input stream",
+                example: r#"echo [[name, value]; ["NAME", "JT"]] | load-env [[name, value]; ["VALUE", "FOO"]]; echo $nu.env.NAME $nu.env.VALUE"#,
+                result: Some(vec![Value::from("JT"), Value::from("UNKNOWN")]),
+            },
+        ]
+    }
+}
+
+fn load_env_from_table(
+    values: impl IntoIterator<Item = Value>,
+    ctx: &EvaluationContext,
+) -> Result<(), ShellError> {
+    for value in values {
+        let mut var_name = None;
+        let mut var_value = None;
+
+        let tag = value.tag();
+
+        for (key, value) in value.row_entries() {
+            if key == "name" {
+                var_name = Some(value.as_string()?);
+            } else if key == "value" {
+                var_value = Some(value.as_string()?);
+            }
+        }
+
+        match (var_name, var_value) {
+            (Some(name), Some(value)) => ctx.scope.add_env_var(name, value),
+            _ => {
+                return Err(ShellError::labeled_error(
+                    r#"Expected each row in the table to have a "name" and "value" field."#,
+                    r#"expected a "name" and "value" field"#,
+                    tag,
+                ))
+            }
+        }
+    }
+
+    Ok(())
+}
+
+pub fn load_env(args: CommandArgs) -> Result<ActionStream, ShellError> {
+    let ctx = EvaluationContext::from_args(&args);
+    let args = args.evaluate_once()?;
+
+    if let Some(values) = args.opt::<Vec<Value>>(0)? {
+        load_env_from_table(values, &ctx)?;
+    }
+
+    load_env_from_table(args.input, &ctx)?;
+
+    Ok(ActionStream::empty())
+}

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

@@ -41,8 +41,8 @@ impl WholeStreamCommand for Ls {
 
     fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
         let name = args.call_info.name_tag.clone();
-        let ctrl_c = args.ctrl_c.clone();
+        let ctrl_c = args.ctrl_c();
-        let shell_manager = args.shell_manager.clone();
+        let shell_manager = args.shell_manager();
         let (args, _) = args.process()?;
         shell_manager.ls(args, name, ctrl_c)
     }

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

@@ -1,352 +1,351 @@
-#[doc(hidden)]
+// #[doc(hidden)]
-#[macro_export]
+// #[macro_export]
-macro_rules! command {
+// macro_rules! command {
-    (
+//     (
-        Named { $export:tt $args:ident $body:block }
+//         Named { $export:tt $args:ident $body:block }
-        Positional { $($number:tt)* }
+//         Positional { $($number:tt)* }
-        Rest {}
+//         Rest {}
-        Signature {
+//         Signature {
-            name: $config_name:tt,
+//             name: $config_name:tt,
-            mandatory_positional: vec![ $($mandatory_positional:tt)* ],
+//             mandatory_positional: vec![ $($mandatory_positional:tt)* ],
-            optional_positional: vec![ $($optional_positional:tt)* ],
+//             optional_positional: vec![ $($optional_positional:tt)* ],
-            rest_positional: $rest_positional:tt,
+//             rest_positional: $rest_positional:tt,
-            named: {
+//             named: {
-                $(
+//                 $(
-                    ($named_param:tt : $named_type:ty : $named_kind:tt)
+//                     ($named_param:tt : $named_type:ty : $named_kind:tt)
-                )*
+//                 )*
-            }
+//             }
-        }
+//         }
 
-        Function {
+//         Function {
-            $( ( $param_name:tt : $param_type:tt ) )*
+//             $( ( $param_name:tt : $param_type:tt ) )*
-        }
+//         }
 
-        Extract {
+//         Extract {
-            $($extract:tt)*
+//             $($extract:tt)*
-        }
+//         }
-    ) => {
+//     ) => {
-        #[allow(non_camel_case_types)]
+//         #[allow(non_camel_case_types)]
-        pub struct $export;
+//         pub struct $export;
 
-        impl Command for $export {
+//         impl Command for $export {
-            fn run(&self, $args: CommandArgs) -> Result<OutputStream, ShellError> {
+//             fn run(&self, $args: CommandArgs) -> Result<OutputStream, ShellError> {
-                fn command($args: EvaluatedCommandArgs, ( $($param_name),*, ): ( $($param_type),*, )) -> Result<OutputStream, ShellError> {
+//                 fn command($args: EvaluatedCommandArgs, ( $($param_name),*, ): ( $($param_type),*, )) -> Result<OutputStream, ShellError> {
-                    let output = $body;
+//                     let output = $body;
 
-                    Ok(output.to_action_stream())
+//                     Ok(output.to_action_stream())
-                }
+//                 }
 
-                let $args = $args.evaluate_once(registry)?;
+//                 let $args = $args.evaluate_once(registry)?;
-                let tuple = ( $($extract ,)* );
+//                 let tuple = ( $($extract ,)* );
-                command( $args, tuple )
+//                 command( $args, tuple )
-            }
+//             }
 
-            fn name(&self) -> &str {
+//             fn name(&self) -> &str {
-                stringify!($config_name)
+//                 stringify!($config_name)
-            }
+//             }
 
-            fn config(&self) -> $nu_parser::registry::Signature {
+//             fn config(&self) -> $nu_parser::registry::Signature {
-                $nu_parser::registry::Signature {
+//                 $nu_parser::registry::Signature {
-                    name: self.name().to_string(),
+//                     name: self.name().to_string(),
-                    positional: vec![$($mandatory_positional)*],
+//                     positional: vec![$($mandatory_positional)*],
-                    rest_positional: false,
+//                     rest_positional: false,
-                    is_filter: false,
+//                     is_filter: false,
-                    is_sink: false,
+//                     is_sink: false,
 
-                    named: {
+//                     named: {
-                        use $nu_parser::registry::NamedType;
+//                         use $nu_parser::registry::NamedType;
 
-                        #[allow(unused_mut)]
+//                         #[allow(unused_mut)]
-                        let mut named: indexmap::IndexMap<String, NamedType> = indexmap::IndexMap::new();
+//                         let mut named: indexmap::IndexMap<String, NamedType> = indexmap::IndexMap::new();
 
-                        $(
+//                         $(
-                            named.insert(stringify!($named_param).to_string(), $nu_parser::registry::NamedType::$named_kind);
+//                             named.insert(stringify!($named_param).to_string(), $nu_parser::registry::NamedType::$named_kind);
-                        )*
+//                         )*
 
-                        named
+//                         named
-                    }
+//                     }
-                }
+//                 }
-            }
+//             }
-        }
+//         }
-    };
+//     };
 
-    // switch
+//     // switch
-    (
+//     (
-        Named { $export:tt $args:ident $body:block }
+//         Named { $export:tt $args:ident $body:block }
-        Positional { $($positional_count:tt)* }
+//         Positional { $($positional_count:tt)* }
-        Rest { -- $param_name:ident : Switch , $($rest:tt)* }
+//         Rest { -- $param_name:ident : Switch , $($rest:tt)* }
-        Signature {
+//         Signature {
-            name: $config_name:tt,
+//             name: $config_name:tt,
-            mandatory_positional: vec![ $($mandatory_positional:tt)* ],
+//             mandatory_positional: vec![ $($mandatory_positional:tt)* ],
-            optional_positional: vec![ $($optional_positional:tt)* ],
+//             optional_positional: vec![ $($optional_positional:tt)* ],
-            rest_positional: $rest_positional:tt,
+//             rest_positional: $rest_positional:tt,
-            named: {
+//             named: {
-                $($config_named:tt)*
+//                 $($config_named:tt)*
-            }
+//             }
-        }
+//         }
-        Function {
+//         Function {
-            $($function:tt)*
+//             $($function:tt)*
-        }
+//         }
-        Extract {
+//         Extract {
-            $($extract:tt)*
+//             $($extract:tt)*
-        }
+//         }
-    ) => {
+//     ) => {
-        command!(
+//         command!(
-            Named { $export $args $body }
+//             Named { $export $args $body }
-            Positional { $($positional_count)* + 1 }
+//             Positional { $($positional_count)* + 1 }
-            Rest { $($rest)* }
+//             Rest { $($rest)* }
-            Signature {
+//             Signature {
-                name: $config_name,
+//                 name: $config_name,
-                mandatory_positional: vec![ $($mandatory_positional)* ],
+//                 mandatory_positional: vec![ $($mandatory_positional)* ],
-                optional_positional: vec![ $($optional_positional)* ],
+//                 optional_positional: vec![ $($optional_positional)* ],
-                rest_positional: $rest_positional,
+//                 rest_positional: $rest_positional,
-                named: {
+//                 named: {
-                    $($config_named)*
+//                     $($config_named)*
-                    ($param_name : Switch : Switch)
+//                     ($param_name : Switch : Switch)
-                }
+//                 }
-            }
+//             }
 
-            Function {
+//             Function {
-                $($function)* ($param_name : Switch)
+//                 $($function)* ($param_name : Switch)
-            }
+//             }
 
-            Extract {
+//             Extract {
-                $($extract)* {
+//                 $($extract)* {
-                    use std::convert::TryInto;
+//                     use std::convert::TryInto;
 
-                    $args.get(stringify!($param_name)).try_into()?
+//                     $args.get(stringify!($param_name)).try_into()?
-                }
+//                 }
-            }
+//             }
-        );
+//         );
-    };
+//     };
 
-    // mandatory named arguments
+//     // mandatory named arguments
-    (
+//     (
-        Named { $export:tt $args:ident $body:block }
+//         Named { $export:tt $args:ident $body:block }
-        Positional { $($positional_count:tt)* }
+//         Positional { $($positional_count:tt)* }
-        Rest { -- $param_name:ident : $param_kind:ty , $($rest:tt)* }
+//         Rest { -- $param_name:ident : $param_kind:ty , $($rest:tt)* }
-        Signature {
+//         Signature {
-            name: $config_name:tt,
+//             name: $config_name:tt,
-            mandatory_positional: vec![ $($mandatory_positional:tt)* ],
+//             mandatory_positional: vec![ $($mandatory_positional:tt)* ],
-            optional_positional: vec![ $($optional_positional:tt)* ],
+//             optional_positional: vec![ $($optional_positional:tt)* ],
-            rest_positional: $rest_positional:tt,
+//             rest_positional: $rest_positional:tt,
-            named: {
+//             named: {
-                $($config_named:tt)*
+//                 $($config_named:tt)*
-            }
+//             }
-        }
+//         }
-        Function {
+//         Function {
-            $($function:tt)*
+//             $($function:tt)*
-        }
+//         }
-        Extract {
+//         Extract {
-            $($extract:tt)*
+//             $($extract:tt)*
-        }
+//         }
-    ) => {
+//     ) => {
-        command!(
+//         command!(
-            Named { $export $args $body }
+//             Named { $export $args $body }
-            Positional { $($positional_count)* + 1 }
+//             Positional { $($positional_count)* + 1 }
-            Rest { $($rest)* }
+//             Rest { $($rest)* }
-            Signature {
+//             Signature {
-                name: $config_name,
+//                 name: $config_name,
-                mandatory_positional: vec![ $($mandatory_positional)* ],
+//                 mandatory_positional: vec![ $($mandatory_positional)* ],
-                optional_positional: vec![ $($optional_positional)* ],
+//                 optional_positional: vec![ $($optional_positional)* ],
-                rest_positional: $rest_positional,
+//                 rest_positional: $rest_positional,
-                named: {
+//                 named: {
-                    $($config_named)*
+//                     $($config_named)*
-                    ($param_name : Mandatory(NamedValue::Single))
+//                     ($param_name : Mandatory(NamedValue::Single))
-                }
+//                 }
-            }
+//             }
 
-            Function {
+//             Function {
-                $($function)* ($param_name : $param_kind)
+//                 $($function)* ($param_name : $param_kind)
-            }
+//             }
 
-            Extract {
+//             Extract {
-                $($extract)* {
+//                 $($extract)* {
-                    use std::convert::TryInto;
+//                     use std::convert::TryInto;
 
-                    $args.get(stringify!($param_name)).try_into()?
+//                     $args.get(stringify!($param_name)).try_into()?
-                }
+//                 }
-            }
+//             }
-        );
+//         );
-    };
+//     };
 
-    // optional named arguments
+//     // optional named arguments
-    (
+//     (
-        Named { $export:tt $args:ident $body:block }
+//         Named { $export:tt $args:ident $body:block }
-        Positional { $($positional_count:tt)* }
+//         Positional { $($positional_count:tt)* }
-        Rest { -- $param_name:ident ? : $param_kind:ty , $($rest:tt)* }
+//         Rest { -- $param_name:ident ? : $param_kind:ty , $($rest:tt)* }
-        Signature {
+//         Signature {
-            name: $config_name:tt,
+//             name: $config_name:tt,
-            mandatory_positional: vec![ $($mandatory_positional:tt)* ],
+//             mandatory_positional: vec![ $($mandatory_positional:tt)* ],
-            optional_positional: vec![ $($optional_positional:tt)* ],
+//             optional_positional: vec![ $($optional_positional:tt)* ],
-            rest_positional: $rest_positional:tt,
+//             rest_positional: $rest_positional:tt,
-            named: {
+//             named: {
-                $($config_named:tt)*
+//                 $($config_named:tt)*
-            }
+//             }
-        }
+//         }
-        Function {
+//         Function {
-            $($function:tt)*
+//             $($function:tt)*
-        }
+//         }
-        Extract {
+//         Extract {
-            $($extract:tt)*
+//             $($extract:tt)*
-        }
+//         }
-    ) => {
+//     ) => {
-        command!(
+//         command!(
-            Named { $export $args $body }
+//             Named { $export $args $body }
-            Positional { $($positional_count)* + 1 }
+//             Positional { $($positional_count)* + 1 }
-            Rest { $($rest)* }
+//             Rest { $($rest)* }
-            Signature {
+//             Signature {
-                name: $config_name,
+//                 name: $config_name,
-                mandatory_positional: vec![ $($mandatory_positional)* ],
+//                 mandatory_positional: vec![ $($mandatory_positional)* ],
-                optional_positional: vec![ $($optional_positional)* ],
+//                 optional_positional: vec![ $($optional_positional)* ],
-                rest_positional: $rest_positional,
+//                 rest_positional: $rest_positional,
-                named: {
+//                 named: {
-                    $($config_named)*
+//                     $($config_named)*
-                    ($param_name : Optional(NamedValue::Single))
+//                     ($param_name : Optional(NamedValue::Single))
-                }
+//                 }
-            }
+//             }
 
-            Function {
+//             Function {
-                $($function)* ($param_name : $param_kind)
+//                 $($function)* ($param_name : $param_kind)
-            }
+//             }
 
-            Extract {
+//             Extract {
-                $($extract)* {
+//                 $($extract)* {
-                    use std::convert::TryInto;
+//                     use std::convert::TryInto;
 
-                    $args.get(stringify!($param_name)).try_into()?
+//                     $args.get(stringify!($param_name)).try_into()?
-                }
+//                 }
-            }
+//             }
-        );
+//         );
-    };
+//     };
 
-    // mandatory positional block
+//     // mandatory positional block
-    (
+//     (
-        Named { $export:ident $args:ident $body:block }
+//         Named { $export:ident $args:ident $body:block }
-        Positional { $($positional_count:tt)* }
+//         Positional { $($positional_count:tt)* }
-        Rest { $param_name:ident : Block , $($rest:tt)* }
+//         Rest { $param_name:ident : Block , $($rest:tt)* }
-        Signature {
+//         Signature {
-            name: $config_name:tt,
+//             name: $config_name:tt,
-            mandatory_positional: vec![ $($mandatory_positional:tt)* ],
+//             mandatory_positional: vec![ $($mandatory_positional:tt)* ],
-            optional_positional: vec![ $($optional_positional:tt)* ],
+//             optional_positional: vec![ $($optional_positional:tt)* ],
-            rest_positional: $rest_positional:tt,
+//             rest_positional: $rest_positional:tt,
-            named: {
+//             named: {
-                $($config_named:tt)*
+//                 $($config_named:tt)*
-            }
+//             }
-        }
+//         }
 
-        Function {
+//         Function {
-            $($function:tt)*
+//             $($function:tt)*
-        }
+//         }
 
-        Extract {
+//         Extract {
-            $($extract:tt)*
+//             $($extract:tt)*
-        }
+//         }
 
-    ) => {
+//     ) => {
-        command!(
+//         command!(
-            Named { $export $args $body }
+//             Named { $export $args $body }
-            Positional { $($positional_count)* + 1 }
+//             Positional { $($positional_count)* + 1 }
-            Rest { $($rest)* }
+//             Rest { $($rest)* }
-            Signature {
+//             Signature {
-                name: $config_name,
+//                 name: $config_name,
-                mandatory_positional: vec![ $($mandatory_positional)* $nu_parser::registry::PositionalType::mandatory_block(
+//                 mandatory_positional: vec![ $($mandatory_positional)* $nu_parser::registry::PositionalType::mandatory_block(
-                    stringify!($param_name)
+//                     stringify!($param_name)
-                ), ],
+//                 ), ],
-                optional_positional: vec![ $($optional_positional)* ],
+//                 optional_positional: vec![ $($optional_positional)* ],
-                rest_positional: $rest_positional,
+//                 rest_positional: $rest_positional,
-                named: {
+//                 named: {
-                    $($config_named)*
+//                     $($config_named)*
-                }
+//                 }
-            }
+//             }
 
-            Function {
+//             Function {
-                $($function)* ($param_name : Block)
+//                 $($function)* ($param_name : Block)
-            }
+//             }
 
-            Extract {
+//             Extract {
-                $($extract:tt)* {
+//                 $($extract:tt)* {
-                    use $nu_data::types::ExtractType;
+//                     use $nu_data::types::ExtractType;
-                    let value = $args.expect_nth($($positional_count)*)?;
+//                     let value = $args.expect_nth($($positional_count)*)?;
-                    Block::extract(value)?
+//                     Block::extract(value)?
-                }
+//                 }
-            }
+//             }
-        );
+//         );
-    };
+//     };
 
+//     // mandatory positional argument
+//     (
+//         Named { $export:ident $args:ident $body:block }
+//         Positional { $($positional_count:tt)* }
+//         Rest { $param_name:ident : $param_kind:ty , $($rest:tt)* }
+//         Signature {
+//             name: $config_name:tt,
+//             mandatory_positional: vec![ $($mandatory_positional:tt)* ],
+//             optional_positional: vec![ $($optional_positional:tt)* ],
+//             rest_positional: $rest_positional:tt,
+//             named: {
+//                 $($config_named:tt)*
+//             }
+//         }
 
-    // mandatory positional argument
+//         Function {
-    (
+//             $($function:tt)*
-        Named { $export:ident $args:ident $body:block }
+//         }
-        Positional { $($positional_count:tt)* }
-        Rest { $param_name:ident : $param_kind:ty , $($rest:tt)* }
-        Signature {
-            name: $config_name:tt,
-            mandatory_positional: vec![ $($mandatory_positional:tt)* ],
-            optional_positional: vec![ $($optional_positional:tt)* ],
-            rest_positional: $rest_positional:tt,
-            named: {
-                $($config_named:tt)*
-            }
-        }
 
-        Function {
+//         Extract {
-            $($function:tt)*
+//             $($extract:tt)*
-        }
+//         }
 
-        Extract {
+//     ) => {
-            $($extract:tt)*
+//         command!(
-        }
+//             Named { $export $args $body }
+//             Positional { $($positional_count)* + 1 }
+//             Rest { $($rest)* }
+//             Signature {
+//                 name: $config_name,
+//                 mandatory_positional: vec![ $($mandatory_positional)* $nu_parser::registry::PositionalType::mandatory(
+//                     stringify!($param_name), <$param_kind>::syntax_type()
+//                 ), ],
+//                 optional_positional: vec![ $($optional_positional)* ],
+//                 rest_positional: $rest_positional,
+//                 named: {
+//                     $($config_named)*
+//                 }
+//             }
 
-    ) => {
+//             Function {
-        command!(
+//                 $($function)* ($param_name : $param_kind)
-            Named { $export $args $body }
+//             }
-            Positional { $($positional_count)* + 1 }
-            Rest { $($rest)* }
-            Signature {
-                name: $config_name,
-                mandatory_positional: vec![ $($mandatory_positional)* $nu_parser::registry::PositionalType::mandatory(
-                    stringify!($param_name), <$param_kind>::syntax_type()
-                ), ],
-                optional_positional: vec![ $($optional_positional)* ],
-                rest_positional: $rest_positional,
-                named: {
-                    $($config_named)*
-                }
-            }
 
-            Function {
+//             Extract {
-                $($function)* ($param_name : $param_kind)
+//                 $($extract:tt)* {
-            }
+//                     use $nu_data::types::ExtractType;
+//                     let value = $args.expect_nth($($positional_count)*)?;
+//                     <$param_kind>::extract(&value)?
+//                 }
+//             }
+//         );
+//     };
 
-            Extract {
+//     ($export:ident as $config_name:tt ( $args:ident , $($command_rest:tt)* ) $body:block) => {
-                $($extract:tt)* {
+//         command!(
-                    use $nu_data::types::ExtractType;
+//             Named { $export $args $body }
-                    let value = $args.expect_nth($($positional_count)*)?;
+//             Positional { 0 }
-                    <$param_kind>::extract(&value)?
+//             Rest { $($command_rest)* }
-                }
+//             Signature {
-            }
+//                 name: $config_name,
-        );
+//                 mandatory_positional: vec![],
-    };
+//                 optional_positional: vec![],
+//                 rest_positional: false,
+//                 named: {}
+//             }
 
-    ($export:ident as $config_name:tt ( $args:ident , $($command_rest:tt)* ) $body:block) => {
+//             Function {
-        command!(
+//             }
-            Named { $export $args $body }
-            Positional { 0 }
-            Rest { $($command_rest)* }
-            Signature {
-                name: $config_name,
-                mandatory_positional: vec![],
-                optional_positional: vec![],
-                rest_positional: false,
-                named: {}
-            }
 
-            Function {
+//             Extract {
-            }
+//             }
-
+//         );
-            Extract {
+//     };
-            }
+// }
-        );
-    };
-}

crates/nu-command/src/commands/math/abs.rs

@@ -20,8 +20,9 @@ impl WholeStreamCommand for SubCommand {
 
     fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         let mapped = args.input.map(move |val| match val.value {
-            UntaggedValue::Primitive(Primitive::Int(val)) => {
+            UntaggedValue::Primitive(Primitive::Int(val)) => UntaggedValue::int(val.abs()).into(),
-                UntaggedValue::int(val.magnitude().clone()).into()
+            UntaggedValue::Primitive(Primitive::BigInt(val)) => {
+                UntaggedValue::big_int(val.magnitude().clone()).into()
             }
             UntaggedValue::Primitive(Primitive::Decimal(val)) => {
                 UntaggedValue::decimal(val.abs()).into()

crates/nu-command/src/commands/math/avg.rs

@@ -5,10 +5,7 @@ use crate::commands::math::utils::run_with_function;
 use nu_engine::WholeStreamCommand;
 
 use nu_errors::ShellError;
-use nu_protocol::{
+use nu_protocol::{hir::Operator, Primitive, Signature, UntaggedValue, Value};
-    hir::{convert_number_to_u64, Number, Operator},
-    Primitive, Signature, UntaggedValue, Value,
-};
 
 use bigdecimal::FromPrimitive;
 
@@ -47,7 +44,7 @@ impl WholeStreamCommand for SubCommand {
 fn to_byte(value: &Value) -> Option<Value> {
     match &value.value {
         UntaggedValue::Primitive(Primitive::Int(num)) => {
-            Some(UntaggedValue::Primitive(Primitive::Filesize(num.clone())).into_untagged_value())
+            Some(UntaggedValue::Primitive(Primitive::Filesize(*num as u64)).into_untagged_value())
         }
         _ => None,
     }
@@ -79,7 +76,7 @@ pub fn average(values: &[Value], name: &Tag) -> Result<Value, ShellError> {
                     Value {
                         value: UntaggedValue::Primitive(Primitive::Filesize(num)),
                         ..
-                    } => UntaggedValue::int(num.clone()).into_untagged_value(),
+                    } => UntaggedValue::int(*num as i64).into_untagged_value(),
                     other => other.clone(),
                 })
                 .collect::<Vec<_>>(),
@@ -100,15 +97,18 @@ pub fn average(values: &[Value], name: &Tag) -> Result<Value, ShellError> {
             value: UntaggedValue::Primitive(Primitive::Filesize(num)),
             ..
         } => {
-            let left = UntaggedValue::from(Primitive::Int(num));
+            let left = UntaggedValue::from(Primitive::Int(num as i64));
             let result = nu_data::value::compute_values(Operator::Divide, &left, &total_rows);
 
             match result {
-                Ok(UntaggedValue::Primitive(Primitive::Decimal(result))) => {
+                Ok(UntaggedValue::Primitive(Primitive::Decimal(result))) => match result.to_u64() {
-                    let number = Number::Decimal(result);
+                    Some(number) => Ok(UntaggedValue::filesize(number).into_value(name)),
-                    let number = convert_number_to_u64(&number);
+                    None => Err(ShellError::labeled_error(
-                    Ok(UntaggedValue::filesize(number).into_value(name))
+                        "could not calculate average of non-integer or unrelated types",
-                }
+                        "source",
+                        name,
+                    )),
+                },
                 Ok(_) => Err(ShellError::labeled_error(
                     "could not calculate average of non-integer or unrelated types",
                     "source",