mike fb72da0e82
unify the *-BuiltinVar parser errors (#8944)
# Description

this pr condenses `MutBuiltinVar`, `LetBuiltinVar` and `ConstBuiltinVar`
into one error:
```nu
Error: nu::parser::name_is_builtin_var

  × `in` used as variable name.
   ╭─[entry #69:1:1]
 1 │ let in = 420
   ·     ─┬
   ·      ╰── already a builtin variable
   ╰────
  help: 'in' is the name of a builtin Nushell variable and cannot be used
        as a variable name
```

it also fixes this case which was previously not handled
```nu
let $nu = 420 # this variable would have been 'lost'
```
2023-04-20 19:44:31 +02:00
..
2023-04-05 13:12:01 -05:00
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.