Files
nushell/crates
132ikl f4136aa3f4 Add pipeline span to metadata (#16014)
# Description

This PR makes the span of a pipeline accessible through `metadata`,
meaning it's possible to get the span of a pipeline without collecting
it.

Examples:
```nushell
ls | metadata
# => ╭────────┬────────────────────╮
# => │        │ ╭───────┬────────╮ │
# => │ span   │ │ start │ 170218 │ │
# => │        │ │ end   │ 170220 │ │
# => │        │ ╰───────┴────────╯ │
# => │ source │ ls                 │
# => ╰────────┴────────────────────╯
```

```nushell
ls | metadata access {|meta|
  error make {msg: "error", label: {text: "here", span: $meta.span}}
}
# => Error:   × error
# =>    ╭─[entry #7:1:1]
# =>  1 │ ls | metadata access {|meta|
# =>    · ─┬
# =>    ·  ╰── here
# =>  2 │   error make {msg: "error", label: {text: "here", span: $meta.span}}
# =>    ╰────
```

Here's an example that wouldn't be possible before, since you would have
to use `metadata $in` to get the span, collecting the (infinite) stream

```nushell
generate {|x=0| {out: 0, next: 0} } | metadata access {|meta|
  # do whatever with stream
  error make {msg: "error", label: {text: "here", span: $meta.span}}
}
# => Error:   × error
# =>    ╭─[entry #16:1:1]
# =>  1 │ generate {|x=0| {out: 0, next: 0} } | metadata access {|meta|
# =>    · ────┬───
# =>    ·     ╰── here
# =>  2 │   # do whatever with stream
# =>    ╰────
```

I haven't done the tests or anything yet since I'm not sure how we feel
about having this as part of the normal metadata, rather than a new
command like `metadata span` or something. We could also have a
`metadata access` like functionality for that with an optional closure
argument potentially.

# User-Facing Changes

* The span of a pipeline is now available through `metadata` and
`metadata access` without collecting a stream.

# Tests + Formatting

TODO

# After Submitting

N/A
2025-06-30 23:17:43 +02:00
..
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.