nushell/crates/nu-protocol
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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Make sure you've run and fixed any issues with these commands:

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- `cargo run -- -c "use std testing; testing run-tests --path
crates/nu-std"` to run the tests for the standard library

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2023-08-20 14:51:35 +02:00
..
src Recursively export constants from modules (#10049) 2023-08-20 14:51:35 +02:00
tests Fix duration type to not report months or years (#9632) 2023-08-08 06:24:09 -05:00
Cargo.toml pin serde to avoid https://github.com/serde-rs/serde/issues/2538 (#10061) 2023-08-20 05:50:26 +12:00
LICENSE Fix rest of license year ranges (#8727) 2023-04-04 09:03:29 +12:00
README.md Add nu-protocol 2021-09-02 13:29:43 +12:00

nu-protocol

The nu-protocol crate holds the definitions of structs/traits that are used throughout Nushell. This gives us one way to expose them to many other crates, as well as make these definitions available to each other, without causing mutually recursive dependencies.