nushell/crates
JT 2c3aade057
Add pattern matching (#8590)
# Description

This adds `match` and basic pattern matching.

An example:

```
match $x {
  1..10 => { print "Value is between 1 and 10" }
  { foo: $bar } => { print $"Value has a 'foo' field with value ($bar)" }
  [$a, $b] => { print $"Value is a list with two items: ($a) and ($b)" }
  _ => { print "Value is none of the above" }
}
```

Like the recent changes to `if` to allow it to be used as an expression,
`match` can also be used as an expression. This allows you to assign the
result to a variable, eg) `let xyz = match ...`

I've also included a short-hand pattern for matching records, as I think
it might help when doing a lot of record patterns: `{$foo}` which is
equivalent to `{foo: $foo}`.

There are still missing components, so consider this the first step in
full pattern matching support. Currently missing:
* Patterns for strings
* Or-patterns (like the `|` in Rust)
* Patterns for tables (unclear how we want to match a table, so it'll
need some design)
* Patterns for binary values
* And much more

# User-Facing Changes

[see above]

# 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` to check that you're using the standard code
style
- `cargo test --workspace` to check that all tests pass

> **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.
2023-03-24 14:52:01 +13:00
..
nu_plugin_custom_values bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu_plugin_example bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu_plugin_formats bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu_plugin_gstat bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu_plugin_inc bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu_plugin_python update nu_plugin_python due to signature changes (#8107) 2023-02-18 13:27:24 +00:00
nu_plugin_query bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu-cli Add pattern matching (#8590) 2023-03-24 14:52:01 +13:00
nu-cmd-lang Add pattern matching (#8590) 2023-03-24 14:52:01 +13:00
nu-color-config Add pattern matching (#8590) 2023-03-24 14:52:01 +13:00
nu-command Add pattern matching (#8590) 2023-03-24 14:52:01 +13:00
nu-engine Add pattern matching (#8590) 2023-03-24 14:52:01 +13:00
nu-explore bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu-glob bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu-json bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu-parser Add pattern matching (#8590) 2023-03-24 14:52:01 +13:00
nu-path bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu-plugin bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu-pretty-hex bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu-protocol Add pattern matching (#8590) 2023-03-24 14:52:01 +13:00
nu-system bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu-table bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu-term-grid bump to 0.77.2 (#8496) 2023-03-17 21:29:15 +13:00
nu-test-support Remove once_cell dependency from nu-test-support create. (#8568) 2023-03-22 19:36:52 +01:00
nu-utils Add pattern matching (#8590) 2023-03-24 14:52:01 +13:00
README.md Remove old nushell/merge engine-q 2022-02-07 14:54:06 -05:00

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.