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fdncred merged 1 commit into from
Apr 26, 2025
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Document pre_execution use of commandline command #1888

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20 changes: 20 additions & 0 deletions book/hooks.md
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Expand Up @@ -98,6 +98,26 @@ $env.SPAM

The hook blocks otherwise follow the general scoping rules, i.e., commands, aliases, etc. defined within the block will be thrown away once the block ends.

## `pre_execution` Hooks

`pre_execution` hooks can inspect the to-be-executed command through the [`commandline` command](/commands/docs/commandline.md).

For example, to print the command being executed:

```nu
$env.config = (
$env.config
| upsert hooks.pre_execution [ {||
$env.repl_commandline = (commandline)
print $"Command: ($env.repl_commandline)"
} ]
)

print (1 + 3)
# => Command: print (1 + 3)
# => 4
```

## Conditional Hooks

One thing you might be tempted to do is to activate an environment whenever you enter a directory:
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