nushell/crates/nu-std
Stefan Holderbach c9e9b138eb
Improve with-env robustness (#12523)
# Description
Work for #7149

- **Error `with-env` given uneven count in list form**
- **Fix `with-env` `CantConvert` to record**
- **Error `with-env` when given protected env vars**
- **Deprecate list/table input of vars to `with-env`**
- **Remove examples for deprecated input**

# User-Facing Changes

## Deprecation of the following forms

```
> with-env [MYENV "my env value"] { $env.MYENV }
my env value

> with-env [X Y W Z] { $env.X }
Y

> with-env [[X W]; [Y Z]] { $env.W }
Z
```

## recommended standardized form

```
# Set by key-value record
> with-env {X: "Y", W: "Z"} { [$env.X $env.W] }
╭───┬───╮
│ 0 │ Y │
│ 1 │ Z │
╰───┴───╯
```

## (Side effect) Repeated definitions in an env shorthand are now
disallowed

```
> FOO=bar FOO=baz $env
Error: nu:🐚:column_defined_twice

  × Record field or table column used twice: FOO
   ╭─[entry #1:1:1]
 1 │ FOO=bar FOO=baz $env
   · ─┬─     ─┬─
   ·  │       ╰── field redefined here
   ·  ╰── field first defined here
   ╰────
```
2024-04-16 19:08:58 +08:00
..
src add a few more logging statements for debugging startup (#12316) 2024-03-28 11:27:12 -05:00
std Improve with-env robustness (#12523) 2024-04-16 19:08:58 +08:00
tests Improve with-env robustness (#12523) 2024-04-16 19:08:58 +08:00
Cargo.toml Bump version to 0.92.3 (#12476) 2024-04-12 08:00:43 -05:00
CONTRIBUTING.md remove the last mention to let-env (#10718) 2023-10-18 23:15:04 +02:00
LICENSE add LICENSE to nu-std (#8803) 2023-04-07 13:39:21 -07:00
README.md fix nu-std README (#11244) 2023-12-06 16:26:02 +01:00
testing.nu Fix testing.nu import of std log (#12392) 2024-04-05 20:29:19 -05:00

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
> scope commands | select name usage | where name =~ "std "
#┬───────────name────────────┬──────────────────────usage──────────────────────
0│std assert                 │Universal assert command
1│std assert equal           │Assert $left == $right
2│std assert error           │Assert that executing the code generates an error
3│std assert greater         │Assert $left > $right
4│std assert greater or equal│Assert $left >= $right
             ...                                     ...
─┴───────────────────────────┴─────────────────────────────────────────────────

🧰 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