hooks.asciidoc

Hooks

Description

Commands can be registered to be executed when certain events arise. To register a hook use the following command:

hook [-group <group> | -once] <scope> <hook_name> <filtering_regex> <commands>

scope can be one of global, buffer or window (See :doc scopes).

hook_name must be one of the hook names in the list below, like InsertKey or BufSetOption.

filtering_regex must match the entire parameter string in order for the commands to be executed.

command is a string containing the commands to execute when the hook is called.

If group is given, make this hook part of the named group. Groups are used for removing hooks with the following command:

remove-hooks <scope> <group>

A call to the command above will remove every hook in scope whose group matches the given group regex.

If -once is given, the hook is automatically removed after running.

For example to automatically use line numbering with .cc files, use the following command:

hook global WinCreate .*\.cc %{ add-highlighter number-lines }

Default hooks

The parameter string associated with each hook is described after the hook name. Hooks with no description will always use an empty string.

NormalIdle

a certain duration has passed since the last keypress in normal mode

NormalKey key

a key is received in normal mode. This hook will not trigger when the user presses a key on the left-hand side of a normal-mode mapping (see :doc mapping), but will trigger for keys on the right-hand side. See also RawKey below.

InsertIdle

a certain duration has passed since the last keypress in insert mode

InsertKey key

a key is received in insert mode. This hook will not trigger when the user presses a key on the left-hand side of a insert-mode mapping (see :doc mapping), but will trigger for keys on the right-hand side. See also RawKey below.

InsertChar char

a character is received in insert mode

InsertDelete deleted char

a character is deleted in insert mode

InsertMove move key

the cursor moved (without inserting) in insert mode

PromptIdle

a certain duration has passed since the last keypress in prompt mode

WinCreate buffer name

a window was created. This hook is executed in draft context, so any changes to selections or input state will be discarded.

WinClose buffer name

a window was destroyed. This hook is executed in a draft context, so any changes to selections or input state will be discarded.

WinResize <line>.<column>

a window was resized. This hook is executed in a draft context, so any changes to selections or input state will be discarded.

WinDisplay buffer name

a client switched to displaying the given buffer.

WinSetOption <option_name>=<new_value>

an option was set in a window context. This hook is executed in a draft context, so any changes to selections or input state will be discarded.

GlobalSetOption <option_name>=<new_value>

an option was set at the global scope

BufSetOption <option_name>=<new_value>

an option was set in a buffer context

BufNewFile filename

a buffer for a new file has been created

BufOpenFile filename

a buffer for an existing file has been created

BufCreate filename

a buffer has been created

BufWritePre filename

executed just before a buffer is written

BufWritePost filename

executed just after a buffer is written

BufReload filename

executed after a buffer reload has been triggered by an external modification to its file

BufClose buffer name

executed when a buffer is deleted, while it is still valid

BufOpenFifo buffer name

executed when a buffer opens a fifo

BufReadFifo <start line>.<start column>,<end line>.<end column>

executed after some data has been read from a fifo and inserted in the buffer. The hook param contains the range of text that was just inserted, in a format compatible with the select command.

BufCloseFifo

executed when a fifo buffer closes its fifo file descriptor either because the buffer is being deleted or the writing end has been closed

ClientCreate client name

executed when a new client is created.

ClientClose client name

executed when a client is closed, after it was removed from the client list.

RuntimeError error message

an error was encountered while executing a user command

ModeChange [push|pop]:<old mode>:<new mode>

Triggered whenever a mode is pushed or removed from the mode stack.

KakBegin session name

kakoune has started, this hook is called just after reading the user configuration files

KakEnd

kakoune is quitting

FocusIn client name

on supported clients, triggered when the client gets focused

FocusOut client name

on supported clients, triggered when the client gets unfocused

InsertCompletionShow

Triggered when the insert completion menu gets displayed

InsertCompletionHide completion

Triggered when the insert completion menu gets hidden, the inserted completion text is passed as filtering text.

RawKey key

Triggered whenever a key is pressed by the user, regardless of what mode Kakoune is in, or what mappings are present (see :doc mapping). It cannot triggered by execute-keys, even with the -with-hooks option (see :doc execeval execute-keys-specific-switches).

ModuleLoaded module

Triggered after a module is evaluated by the first require-module call

Note that some hooks will not consider underlying scopes depending on what context they are bound to be run into, e.g. the BufWritePost hook is a buffer hook, and will not consider the window scope.

While defining hook commands with a %sh{} block, some additional env vars are available:

• kak_hook_param: filtering text passed to the currently executing hook

• kak_hook_param_capture_N: text captured by the hook filter regex capturing group N, N can either be the capturing group number, or its name (See :doc regex groups).

Disabling Hooks

Any normal mode command can be prefixed with \ ` which will disable hook execution for the duration for the command (including the duration of modes the command could move to, so `\i will disable hooks for the whole insert session).

As autoindentation is implemented in terms of hooks, this can be used to disable it when pasting text.

A less temporary alternative is to set the disabled_hooks option which accepts a regex describing which hooks won’t be executed. For example indentation hooks can be disabled with '.*-indent'.

Finally, hook execution can be disabled while using the execute-keys or evaluate-commands commands by using the -no-hooks switch. (See :doc execeval)

As an exception to these rules, hooks declared with the -always switch are triggered no matter what. A good use case is doing some cleanup on BufCloseFifo.