Zle

Zle, short for Zsh Line Editor, is the interactive line editor used by the Z shell (zsh) to manage command-line input. It handles editing, cursor movement, insertion and deletion of text, and the execution of commands. Zle operates within a zsh session and is responsible for the real-time editing experience that users see in the command prompt. It does not run as a separate process.

Zle provides support for multiple editing styles, most notably Emacs and Vi keybindings. Users switch between modes with key bindings such as bindkey -e for Emacs style or bindkey -v for Vi style. The line editor integrates with zsh features like command history and programmable completion, enabling efficient command entry and navigation.

A key feature of Zle is its extensibility through widgets. Widgets are small, executable pieces of code that perform editing tasks or modify the prompt. Built-in widgets cover common operations such as moving the cursor, editing words, and navigating history. Users can create custom widgets by defining a shell function and registering it as a widget with zle -N function_name. The new widget can then be bound to a key sequence using bindkey, enabling bespoke behavior during command entry.

In practical use, users customize Zle in their shell startup files (for example, .zshrc) to set the preferred editing mode, define custom widgets, or assign soft keys to frequently used actions. This makes Zle adaptable to a range of workflows, from simple command entry to advanced line editing setups.

See also: Z shell, bindkey, zsh widgets, command history, command-line editing.