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export def-env for core

Define a custom command that participates in the environment and export it from a module.

Signature

> export def-env {flags} (name) (params) (block)

Parameters

  • name: definition name
  • params: parameters
  • block: body of the definition

Input/output types:

input output
nothing nothing

Examples

Define a custom command that participates in the environment in a module and call it

>modulefoo { export def-envbar [] { $env.FOO_BAR="BAZ" } };usefoobar;bar;$env.FOO_BAR
BAZ

Notes

This command is a parser keyword. For details, check:
  https://www.nushell.sh/book/thinking_in_nu.html

=== EXTRA NOTE ===
All blocks are scoped, including variable definition and environment variable changes.

Because of this, the following doesn't work:

export def-env cd_with_fallback [arg = ""] {
    let fall_back_path = "/tmp"
    if $arg != "" {
        cd $arg
    } else {
        cd $fall_back_path
    }
}

Instead, you have to use cd in the top level scope:

export def-env cd_with_fallback [arg = ""] {
    let fall_back_path = "/tmp"
    let path = if $arg != "" {
        $arg
    } else {
        $fall_back_path
    }
    cd $path
}

Copyright © 2019–2023 The Nushell Project DevelopersLicensed under the MIT License.
https://www.nushell.sh/commands/docs/export_def-env.html