Reverts nushell/nushell#8310
In anticipation that we may want to revert this PR. I'm starting the
process because of this issue.
This stopped working
```
let-env NU_LIB_DIRS = [
($nu.config-path | path dirname | path join 'scripts')
'C:\Users\username\source\repos\forks\nu_scripts'
($nu.config-path | path dirname)
]
```
You have to do this now instead.
```
const NU_LIB_DIRS = [
'C:\Users\username\AppData\Roaming\nushell\scripts'
'C:\Users\username\source\repos\forks\nu_scripts'
'C:\Users\username\AppData\Roaming\nushell'
]
```
In talking with @kubouch, he was saying that the `let-env` version
should keep working. Hopefully it's a small change.
# Description
Allow NU_LIBS_DIR and friends to be const they can be updated within the
same parse pass. This will allow us to remove having multiple config
files eventually.
Small implementation detail: I've changed `call.parser_info` to a
hashmap with string keys, so the information can have names rather than
indices, and we don't have to worry too much about the order in which we
put things into it.
Closes https://github.com/nushell/nushell/issues/8422
# User-Facing Changes
In a single file, users can now do stuff like
```
const NU_LIBS_DIR = ['/some/path/here']
source script.nu
```
and the source statement will use the value of NU_LIBS_DIR declared the
line before.
Currently, if there is no `NU_LIBS_DIR` const, then we fallback to using
the value of the `NU_LIBS_DIR` env-var, so there are no breaking changes
(unless someone named a const NU_LIBS_DIR for some reason).
![2023-03-04-014103_hyprshot](https://user-images.githubusercontent.com/13265529/222885263-135cdd0d-7884-438b-b2ed-c3979fa44463.png)
# Tests + Formatting
~~TODO: write tests~~ Done
# After Submitting
~~TODO: update docs~~ Will do when we update default_env.nu/merge
default_env.nu into default_config.nu.
Continuation of #8229 and #8326
# Description
The `ShellError` enum at the moment is kind of messy.
Many variants are basic tuple structs where you always have to reference
the implementation with its macro invocation to know which field serves
which purpose.
Furthermore we have both variants that are kind of redundant or either
overly broad to be useful for the user to match on or overly specific
with few uses.
So I set out to start fixing the lacking documentation and naming to
make it feasible to critically review the individual usages and fix
those.
Furthermore we can decide to join or split up variants that don't seem
to be fit for purpose.
# Call to action
**Everyone:** Feel free to add review comments if you spot inconsistent
use of `ShellError` variants.
# User-Facing Changes
(None now, end goal more explicit and consistent error messages)
# Tests + Formatting
(No additional tests needed so far)
# Commits (so far)
- Remove `ShellError::FeatureNotEnabled`
- Name fields on `SE::ExternalNotSupported`
- Name field on `SE::InvalidProbability`
- Name fields on `SE::NushellFailed` variants
- Remove unused `SE::NushellFailedSpannedHelp`
- Name field on `SE::VariableNotFoundAtRuntime`
- Name fields on `SE::EnvVarNotFoundAtRuntime`
- Name fields on `SE::ModuleNotFoundAtRuntime`
- Remove usused `ModuleOrOverlayNotFoundAtRuntime`
- Name fields on `SE::OverlayNotFoundAtRuntime`
- Name field on `SE::NotFound`
* Initial implementation of ordered call args
* Run cargo fmt
* Fix some clippy lints
* Add positional len and nth
* Cargo fmt
* Remove more old nth calls
* Good ole rustfmt
* Add named len
Co-authored-by: Hristo Filaretov <h.filaretov@protonmail.com>