nushell/crates/nu-parser/src
JT 53ae03bd63
Custom command input/output types (#9690)
# 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
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> **Note**
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# After Submitting
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2023-07-15 09:51:28 +12:00
..
deparse.rs allow empty string arguments (#9420) 2023-06-13 07:30:30 -05:00
eval.rs Fix broken constants in scopes (#9679) 2023-07-14 00:02:05 +03:00
flatten.rs Avoid blocking when o+e> redirects too much stderr message (#8784) 2023-05-17 17:47:03 -05:00
known_external.rs Document and critically review ShellError variants - Ep. 3 (#8340) 2023-03-06 18:33:09 +01:00
lex.rs allow comment in multiple line pipeline (#9436) 2023-06-15 13:11:42 +02:00
lib.rs Add virtual path abstraction layer (#9245) 2023-05-23 23:48:50 +03:00
lite_parser.rs Let with pipeline (#9589) 2023-07-03 17:45:10 +12:00
parse_keywords.rs Custom command input/output types (#9690) 2023-07-15 09:51:28 +12:00
parse_patterns.rs Cut down on unnecessary parsing for SyntaxShape::Any (#9280) 2023-05-25 07:53:57 +12:00
parser.rs Custom command input/output types (#9690) 2023-07-15 09:51:28 +12:00
parser_path.rs Add virtual path abstraction layer (#9245) 2023-05-23 23:48:50 +03:00
type_check.rs Custom command input/output types (#9690) 2023-07-15 09:51:28 +12:00