nushell/crates
Devyn Cairns 872aa78373
Add interleave command for reading multiple streams in parallel (#11955)
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# Description
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Thank you for improving Nushell. Please, check our [contributing
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This command mixes input from multiple sources and sends items to the
final stream as soon as they're available. It can be called as part of a
pipeline with input, or it can take multiple closures and mix them that
way.

See `crates/nu-command/tests/commands/interleave.rs` for a practical
example. I imagine this will be most often used to run multiple commands
in parallel and print their outputs line-by-line. A stdlib command could
potentially use `interleave` to make this particular use case easier.

It's quite common to wish that nushell had a command for running things
in the background, and instead of providing job control, this provides
an alternative to some use cases for that by just allowing multiple
commands to run simultaneously and direct their output to the same
place.

This enables certain things that are not possible with `par-each` - for
example, you may wish to run `make` across several projects in parallel:

```nushell
(ls projects).name | par-each { |project| cd $project; make }
```

This works well enough, but the output will only be available after each
`make` command finishes. `interleave` allows you to get each line:

```nushell
interleave ...(
  (ls projects).name | each { |project|
    {
      cd $project
      make | lines | each { |line| {project: $project, out: $line} }
    }
  }
)
```

The result of this is a stream that you could process further - for
example, by saving to a text file.

Note that the closures themselves are not run in parallel. The initial
execution happens serially, and then the streams are consumed in
parallel.

# User-Facing Changes
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Adds a new command.

# Tests + Formatting
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crates/nu-std"` to run the tests for the standard library

> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
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- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
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2024-03-01 16:56:37 -06:00
..
nu-cli Fix completions for directories with hidden files (#11921) 2024-02-26 12:14:19 -06:00
nu-cmd-base remove unused dependencies (#11938) 2024-02-22 16:31:37 -06:00
nu-cmd-dataframe Add columns to dataframe that are present in the schema but not present the Dataframe when applying schema. (#11987) 2024-02-26 17:22:33 -06:00
nu-cmd-extra add binary data handling to bits commands (#11854) 2024-02-28 20:43:50 +08:00
nu-cmd-lang Glob: don't allow implicit casting between glob and string (#11992) 2024-02-28 23:05:35 +08:00
nu-color-config open, rm, umv, cp, rm and du: Don't globs if inputs are variables or string interpolation (#11886) 2024-02-23 09:17:09 +08:00
nu-command Add interleave command for reading multiple streams in parallel (#11955) 2024-03-01 16:56:37 -06:00
nu-engine Remove some unnecessary static Vecs (#11947) 2024-02-24 20:58:01 +01:00
nu-explore Add Value::coerce_str (#11885) 2024-02-18 17:47:10 +01:00
nu-glob bump to dev release of nushell 0.90.2 (#11793) 2024-02-07 16:26:03 -06:00
nu-json bump to dev release of nushell 0.90.2 (#11793) 2024-02-07 16:26:03 -06:00
nu-lsp remove unused dependencies (#11938) 2024-02-22 16:31:37 -06:00
nu-parser Glob: don't allow implicit casting between glob and string (#11992) 2024-02-28 23:05:35 +08:00
nu-path bump to dev release of nushell 0.90.2 (#11793) 2024-02-07 16:26:03 -06:00
nu-plugin Plugin StreamReader: fuse the iterator after an error (#12027) 2024-02-29 23:39:17 +01:00
nu-pretty-hex bump to dev release of nushell 0.90.2 (#11793) 2024-02-07 16:26:03 -06:00
nu-protocol Glob: don't allow implicit casting between glob and string (#11992) 2024-02-28 23:05:35 +08:00
nu-std open, rm, umv, cp, rm and du: Don't globs if inputs are variables or string interpolation (#11886) 2024-02-23 09:17:09 +08:00
nu-system bump to dev release of nushell 0.90.2 (#11793) 2024-02-07 16:26:03 -06:00
nu-table Bump fancy-regex from 0.12.0 to 0.13.0 (#11893) 2024-02-19 09:54:37 +08:00
nu-term-grid bump to dev release of nushell 0.90.2 (#11793) 2024-02-07 16:26:03 -06:00
nu-test-support Bump tempfile from 3.9.0 to 3.10.0 (#11977) 2024-02-26 15:38:11 +08:00
nu-utils fix format date based on users locale (#11908) 2024-02-20 11:08:49 -06:00
nu_plugin_custom_values Bidirectional communication and streams for plugins (#11911) 2024-02-25 16:32:50 -06:00
nu_plugin_example Remove Record::from_raw_cols_vals_unchecked (#11810) 2024-02-18 14:20:22 +02:00
nu_plugin_formats Add Value::coerce_str (#11885) 2024-02-18 17:47:10 +01:00
nu_plugin_gstat Name the Value conversion functions more clearly (#11851) 2024-02-17 18:14:16 +00:00
nu_plugin_inc Name the Value conversion functions more clearly (#11851) 2024-02-17 18:14:16 +00:00
nu_plugin_python Add Goodbye message to ensure plugins exit when they are no longer needed (#12014) 2024-02-28 20:41:22 -06:00
nu_plugin_query Add Value::coerce_str (#11885) 2024-02-18 17:47:10 +01:00
nu_plugin_stream_example Bidirectional communication and streams for plugins (#11911) 2024-02-25 16:32:50 -06:00
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.