nushell/crates/nu-std
Bob Hyman 8e7405bf49
std dirs simply stays in sync with CD changes to PWD (#9267)
# Description
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Fixes https://github.com/nushell/nushell/issues/9229.
Supersedes #9234

The reported problem was that `shells` list of active shells (a.k.a `std
dirs show` would show an inaccurate active
working directory if user changed it via `cd` command.

The fix here is for the `std dirs` module to let `$env.PWD` mask the
active slot of `$env.DIRS_LIST`. The user is free to invoke CD (or write
to `$env.PWD`) and `std dirs show` will display that as the active
working directory.

When user changes the active slot (via `n`, `p`, `add` or `drop`) `std
dirs` remembers the then current PWD in the about-to-be-vacated active
slot in `$env.DIRS_LIST`, so it is there if you come back to that slot.

# User-Facing Changes
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None. It just works™️

# Tests + Formatting
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2023-05-23 06:24:39 -05:00
..
lib std dirs simply stays in sync with CD changes to PWD (#9267) 2023-05-23 06:24:39 -05:00
src FEATURE: fix the namespace of the standard library (not testing) (#9193) 2023-05-19 23:27:45 +03:00
tests std dirs simply stays in sync with CD changes to PWD (#9267) 2023-05-23 06:24:39 -05:00
Cargo.toml bump nushell from release version to development version (#9215) 2023-05-17 07:59:01 -05:00
CONTRIBUTING.md refactor the CONTRIBUTING.md guidelines for nu-std (#8912) 2023-04-19 22:21:27 +02:00
LICENSE add LICENSE to nu-std (#8803) 2023-04-07 13:39:21 -07:00
README.md refactor the CONTRIBUTING.md guidelines for nu-std (#8912) 2023-04-19 22:21:27 +02:00

Welcome to the standard library of `nushell`!

The standard library is a pure-nushell collection of custom commands which provide interactive utilities and building blocks for users writing casual scripts or complex applications.

To see what's here:

> use std
> help commands | select name usage | where name =~ "std "
╭────┬─────────────────────────────┬────────────────────────────────────────────────────────────────╮
│  # │            name             │                                usage                           │
├────┼─────────────────────────────┼────────────────────────────────────────────────────────────────┤
│  0 │ std assert                  │ Universal assert command                                       │
│  1 │ std assert equal            │ Assert $left == $right                                         │
           . . .
│ 11 │ std clip                    │ put the end of a pipe into the system clipboard.               │
│ 12 │ std dirs add                │ Add one or more directories to the list.                       │
           . . .
├────┼─────────────────────────────┼────────────────────────────────────────────────────────────────┤
│  # │            name             │                                usage                           │
╰────┴─────────────────────────────┴────────────────────────────────────────────────────────────────╯

🧰 Using the standard library in the REPL or in scripts

All commands in the standard library must be "imported" into the running environment (the interactive read-execute-print-loop (REPL) or a .nu script) using the use command.

You can choose to import the whole module, but then must refer to individual commands with a std prefix, e.g:

use std

std log debug "Running now"
std assert (1 == 2)

Or you can enumerate the specific commands you want to import and invoke them without the std prefix.

use std ["log debug" assert]

log debug "Running again"
assert (2 == 1)

This is probably the form of import you'll want to add to your env.nu for interactive use.

✏️ contribute to the standard library

You're invited to contribute to the standard library! See CONTRIBUTING.md for details