nushell/crates/nu-cmd-lang/src
Jakub Žádník 3148acd3a4
Recursively export constants from modules (#10049)
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# Description
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https://github.com/nushell/nushell/pull/9773 introduced constants to
modules and allowed to export them, but only within one level. This PR:
* allows recursive exporting of constants from all submodules
* fixes submodule imports in a list import pattern
* makes sure exported constants are actual constants

Should unblock https://github.com/nushell/nushell/pull/9678

### Example:
```nushell
module spam {
    export module eggs {
        export module bacon {
            export const viking = 'eats'
        }
    }
}

use spam 
print $spam.eggs.bacon.viking  # prints 'eats'

use spam [eggs]
print $eggs.bacon.viking  # prints 'eats'

use spam eggs bacon viking
print $viking  # prints 'eats'
```

### Limitation 1:

Considering the above `spam` module, attempting to get `eggs bacon` from
`spam` module doesn't work directly:
```nushell
use spam [ eggs bacon ]  # attempts to load `eggs`, then `bacon`
use spam [ "eggs bacon" ]  # obviously wrong name for a constant, but doesn't work also for commands
```

Workaround (for example):
```nushell
use spam eggs
use eggs [ bacon ]

print $bacon.viking  # prints 'eats'
```

I'm thinking I'll just leave it in, as you can easily work around this.
It is also a limitation of the import pattern in general, not just
constants.

### Limitation 2:

`overlay use` successfully imports the constants, but `overlay hide`
does not hide them, even though it seems to hide normal variables
successfully. This needs more investigation.

# User-Facing Changes
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Allows recursive constant exports from submodules.

# Tests + Formatting
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2023-08-20 14:51:35 +02:00
..
core_commands Recursively export constants from modules (#10049) 2023-08-20 14:51:35 +02:00
default_context.rs Allow exporting extern-wrapped (#10025) 2023-08-18 20:45:33 +03:00
example_support.rs Remove Signature.vectorizes_over_list entirely (#9777) 2023-07-26 23:34:43 +02:00
example_test.rs Remove Signature.vectorizes_over_list entirely (#9777) 2023-07-26 23:34:43 +02:00
lib.rs cratification: Example support (#8231) 2023-02-27 13:58:56 -08:00