mirror of
https://github.com/nushell/nushell.git
synced 2025-05-13 11:14:33 +00:00
53ae03bd63
# Description
This adds input/output types to custom commands. These are input/output
pairs that related an input type to an output type.
For example (a single int-to-int input/output pair):
```
def foo []: int -> int { ... }
```
You can also have multiple input/output pairs:
```
def bar []: [int -> string, string -> list<string>] { ... }
```
These types are checked during definition time in the parser. If the
block does not match the type, the user will get a parser error.
This `:` to begin the input/output signatures should immediately follow
the argument signature as shown above.
The PR also improves type parsing by re-using the shape parser. The
shape parser is now the canonical way to parse types/shapes in user
code.
This PR also splits `extern` into `extern`/`extern-wrapped` because of
the parser limitation that a multi-span argument (which Signature now
is) can't precede an optional argument. `extern-wrapped` now takes the
required block that was previously optional.
# User-Facing Changes
The change to `extern` to split into `extern` and `extern-wrapped` is a
breaking change.
# 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 -- -c "use std testing; testing run-tests --path
crates/nu-std"` 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 Submitting
<!-- If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
-->
Nushell core libraries and plugins
These sub-crates form both the foundation for Nu and a set of plugins which extend Nu with additional functionality.
Foundational libraries are split into two kinds of crates:
- Core crates - those crates that work together to build the Nushell language engine
- Support crates - a set of crates that support the engine with additional features like JSON support, ANSI support, and more.
Plugins are likewise also split into two types:
- Core plugins - plugins that provide part of the default experience of Nu, including access to the system properties, processes, and web-connectivity features.
- Extra plugins - these plugins run a wide range of different capabilities like working with different file types, charting, viewing binary data, and more.