# Setting up bash completion

This guide walks through setting up conda tab completion in bash.

## Prerequisites

- conda 25.1 or later
- bash 4.0 or later. Bash 4.4 or later preserves completion ordering
  more consistently because it supports `compopt -o nosort`.

## Install conda-completion

```bash
conda install -c conda-forge conda-completion
```

## Activate completion

### Option A: automatic install

```bash
conda completion install
```

This detects the current shell and adds a delimited block to your
`~/.bashrc` (or `~/.bash_profile` if that exists). Preview with
`--dry-run`:

```bash
conda completion install --dry-run
```

### Option B: manual setup

Add this line to your `~/.bashrc`:

```bash
eval "$(conda completion init bash)"
```

## Verify

Open a new terminal (or run `source ~/.bashrc`) and try:

:::{image} ../../demos/install.gif
:alt: conda-completion install demo
:width: 100%
:::

```text
$ conda <TAB><TAB>
activate     clean        config       create       ...
install      list         remove       update       ...

$ conda inst<TAB>
$ conda install

$ conda install --<TAB>
--channel     --dry-run     --name        --prefix      ...
```

## How it works in bash

The generated script defines a `_conda_completion` function and registers
it via `complete -o default -F _conda_completion conda`. On each TAB
press, bash calls this function which invokes the Rust binary with:

- `${COMP_WORDS[@]}` (the current command line words)
- `$COMP_CWORD` (the index of the word being completed)

The binary returns one candidate per line and bash populates `COMPREPLY`.

## Uninstall

```bash
conda completion uninstall
```

This removes the delimited block from your RC file, leaving everything
else intact.