zsh-completions/zsh-completions-howto.org

• Intro
  • Defining completion functions
• Utility functions with example code
  • compadd
  • _gnu_generic
  • _arguments
  • _regex_arguments
  • _regex_words
  • _values
  • _comma_separated
  • _files
  • _net_interfaces
• gotchas
• Putting it all together
• Other resources

Intro

The official documentation for writing zsh completion functions is difficult to understand, and doesn't give many examples. At the time of writing this document I was able to find two other tutorials on the web, however both of those tutorials only explain a small portion of the capabilities of the completion system. This document aims to give more complete and easy to understand explanation for creating zsh completion functions. I do not go into all the details, but will give enough information and examples to get you up and running. If you need more details you can look it up for yourself in the official documentation.

Please make any scripts that you create publically available for others (e.g. by forking this repo and making a pull request).

Defining completion functions

Completion functions for commands are stored in files with names beginning with an underscore _, and these files should be placed in a directory listed in the $fpath variable. You can add a directory to $fpath by adding a line like this to your ~/.zshrc file:

fpath=(~/newdir $fpath)

The first line of a completion function file can look something like this:

#compdef foobar

This tells zsh that the file contains code for completing the foobar command. This is the format that you will use most often for the first line, but you can also use the same file for completing several different functions if you want. See here for more details.

You can also use the compdef command directly on the command line to tell zsh which function to use for completing a command like this:

> compdef _function foobar

or if you want to supply arguments:

> compdef '_function arg1 arg2' foobar

See here for more details.

Utility functions with example code

compadd

_gnu_generic

_arguments

_regex_arguments

_regex_words

_values

_comma_separated

_files

_net_interfaces

gotchas

Putting it all together

Other resources

Here is a nicely formatted short tutorial showing basic usage of the _arguments function, and here is a slightly more advanced tutorial using the _arguments function. Here is the zshcompsys man page.