4af24363c2
# Description For years, Nushell has used `let-env` to set a single environment variable. As our work on scoping continued, we refined what it meant for a variable to be in scope using `let` but never updated how `let-env` would work. Instead, `let-env` confusingly created mutations to the command's copy of `$env`. So, to help fix the mental model and point people to the right way of thinking about what changing the environment means, this PR removes `let-env` to encourage people to think of it as updating the command's environment variable via mutation. Before: ``` let-env FOO = "BAR" ``` Now: ``` $env.FOO = "BAR" ``` It's also a good reminder that the environment owned by the command is in the `$env` variable rather than global like it is in other shells. # User-Facing Changes BREAKING CHANGE BREAKING CHANGE This completely removes `let-env FOO = "BAR"` so that we can focus on `$env.FOO = "BAR"`. # Tests + Formatting <!-- Don't forget to add tests that cover your changes. Make sure you've run and fixed any issues with these commands: - `cargo fmt --all -- --check` to check standard code formatting (`cargo fmt --all` applies these changes) - `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A clippy::needless_collect -A clippy::result_large_err` to check that you're using the standard code style - `cargo test --workspace` to check that all tests pass - `cargo run -- crates/nu-std/tests/run.nu` to run the tests for the standard library > **Note** > from `nushell` you can also use the `toolkit` as follows > ```bash > use toolkit.nu # or use an `env_change` hook to activate it automatically > toolkit check pr > ``` --> # After / Before Submitting integration scripts to update: - ✔️ [starship](https://github.com/starship/starship/blob/master/src/init/starship.nu) - ✔️ [virtualenv](https://github.com/pypa/virtualenv/blob/main/src/virtualenv/activation/nushell/activate.nu) - ✔️ [atuin](https://github.com/ellie/atuin/blob/main/atuin/src/shell/atuin.nu) (PR: https://github.com/ellie/atuin/pull/1080) - ❌ [zoxide](https://github.com/ajeetdsouza/zoxide/blob/main/templates/nushell.txt) (PR: https://github.com/ajeetdsouza/zoxide/pull/587) - ✔️ [oh-my-posh](https://github.com/JanDeDobbeleer/oh-my-posh/blob/main/src/shell/scripts/omp.nu) (pr: https://github.com/JanDeDobbeleer/oh-my-posh/pull/4011) |
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src | ||
std | ||
tests | ||
Cargo.toml | ||
CONTRIBUTING.md | ||
LICENSE | ||
README.md |
Welcome to the standard library of `nushell`!
The standard library is a pure-nushell
collection of custom commands which
provide interactive utilities and building blocks for users writing casual scripts or complex applications.
To see what's here:
> use std
> help commands | select name usage | where name =~ "std "
╭────┬─────────────────────────────┬────────────────────────────────────────────────────────────────╮
│ # │ name │ usage │
├────┼─────────────────────────────┼────────────────────────────────────────────────────────────────┤
│ 0 │ std assert │ Universal assert command │
│ 1 │ std assert equal │ Assert $left == $right │
. . .
│ 11 │ std clip │ put the end of a pipe into the system clipboard. │
│ 12 │ std dirs add │ Add one or more directories to the list. │
. . .
├────┼─────────────────────────────┼────────────────────────────────────────────────────────────────┤
│ # │ name │ usage │
╰────┴─────────────────────────────┴────────────────────────────────────────────────────────────────╯
🧰 Using the standard library in the REPL or in scripts
All commands in the standard library must be "imported" into the running environment
(the interactive read-execute-print-loop (REPL) or a .nu
script) using the
use
command.
You can choose to import the whole module, but then must refer to individual commands with a std
prefix, e.g:
use std
std log debug "Running now"
std assert (1 == 2)
Or you can enumerate the specific commands you want to import and invoke them without the std
prefix.
use std ["log debug" assert]
log debug "Running again"
assert (2 == 1)
This is probably the form of import you'll want to add to your env.nu
for interactive use.
✏️ contribute to the standard library
You're invited to contribute to the standard library! See CONTRIBUTING.md for details