forked from extern/nushell
7b89fab327
# Description
This PR adds new flag `--keep-order/-k` for the `par_each` filter. This
flag keeps sequence of output same as the order of input.
Output without the flag:
```nu
> 1..6 | par-each {|n| $n * 2 }
╭────╮
│ 4 │
│ 10 │
│ 2 │
│ 8 │
│ 12 │
│ 6 │
╰────╯
```
Output with the `--keep-order` flag:
```nu
> 1..6 | par-each --keep-order {|n| $n * 2 }
╭────╮
│ 2 │
│ 4 │
│ 6 │
│ 8 │
│ 10 │
│ 12 │
╰────╯
```
I think the presence of this flag is justified, since:
- Much easier to use than `.. | enumerate | par-each {|p| update item
..} | sort-by index | get item`
- Faster, as it uses internally parallel sorting in the same thread pool
A note about naming: it may conflict with `--keep-empty/-k` flag of the
`each` filter if the same feature will be used in `par-each`, so maybe
it needs some other name.
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.