Hooks are arrays of functions that happen automatically when events occur in your shell.
The hooks that are frequently used are chpwd, precmd, preexec, and zshaddhistory.
precmd is executed before your prompt is displayed and is often used to set values in your [$PROMPT'](prompt.md). preexecis executed between when you pressenter` on a command prompt but before the command is executed.
Each hook is an array of widgets which are executed by zsh. To display what widgets are in each of your hooks you can use the zhooks function.
If you want to extend your hooks you can easily do it with the add-zsh-hook which should be available in most zsh packages.
# create a do-ls function
# Make sure to use emulate -L zsh or
# your shell settings and a directory
# named 'rm' could be deadly
do-ls() {emulate -L zsh; ls;}
# add do-ls to chpwd hook
add-zsh-hook chpwd do-ls
cd ~/
Desktop Music
Documents Pictures
Downloads PublicYou may need to play with which hook to use and your function definition to get it just right. Many prompt themes will automatically install hooks for you.
Sometimes it would be helpful if a widget was a hook. This would allow the widget to run multiple functions when invoked.
You could redefine widgets like zle-line-init and zle-keymap-select with user widgets but that makes it hard to combine smaller functions.
Instead, you can create a custom hook and redefine the widget to invoke your hook. Then you can add/remove functions to the hook as needed.
For that you can use hooks-define-hook and hooks-add-hook from the same plugin.