Kakoune

Introduction:

Kakoune is a code editor heavily inspired by vim, as such most of it’s commands are similar to vi’s ones.

Kakoune can operate in two modes, normal and insertion. In insertion mode, keys are directly inserted into the current buffer. In normal mode, keys are used to manipulate the current selection and to enter insertion mode.

There is no concept of cursor in kakoune, only selections, a single character selection can be seen as a cursor but there is no difference internally.

Building

Kakoune dependencies are:

• GCC >= 4.6

• boost

• ncurses

To build, just type make in the src directory

Basic Movement

• space: select the character under selection end

• h: select the character on the right of selection end

• j: select the character below the selection end

• k: select the character above the selection end

• l: select the character on the left of selection end

• w: select the word and following whitespaces on the right of selection end

• b: select preceding whitespaces and the word on the left of selection end

• e: select preceding whitespaces and the word on the right of selection end

• x: select line on which selection end lies (or next line when end lies on an end-of-line)

• alt-x: expand selections to contain full lines (including end-of-lines)

• %: select whole buffer

• alt-H: select to line begin

• alt-L: select to line end

Appending

for most selection commands, using shift permits to add to current selection instead of replacing it. for example, wWW selects 3 consecutive words

Using Counts

Most selection commands also support counts, which are entered before the command itself.

for example, 3W selects 3 consecutive words and 3w select the third word on the right of selection end.

Changes

• i: insert before current selection

• a: insert after current selection

• d: yank and delete current selection

• c: yank and delete current selection and insert

• I: insert at current selection begin line start

• A: insert at current selection end line end

• o: insert in a new line below current selection end

• O: insert in a new line above current selection begin

• p: paste after current selection end

• P: paste before current selection begin

• alt-j: join selected lines

• |: pipe each selections through the given external filter program and replace with it’s output.

Multi Selection

Kak was designed from the start to handle multiple selections. On way to get a multiselection is via the s key.

For example, to change all occurences of word roger to word marcel in a paragraph, here is what can be done:

select the paragraph with enough x. press s and enter roger then enter. now paragraph selection was replaced with multiselection of each roger in the paragraph. press c and marcel<esc> to replace rogers with marcels.

A multiselection can also be obtained with Alt-s, which splits the current selection according to the regex entered. To split a comma separated list, use alt-s then , *

To clear multiple selections, use space.

Registers

registers are named list of text. They are used for various purpose, like storing the last yanked test, or the captures groups associated with the last selection.

While in insert mode, ctrl-r followed by a register name (one character) inserts it.

For example, ctrl-r followed by " will insert the currently yanked text. ctrl-r followed by 2 will insert the second capture group from the last regex selection.

Registers are lists, instead of simply text in order to interact well with multiselection. Each selection have it’s own captures, or yank buffer.

Highlighters

Manipulation of the displayed text is done through highlighters, which can be added or removed with the command :addhl <highlighter_name> <highlighter_parameters…​> and :rmhl <highlighter_id>

existing highlighters are:

• highlight_selections: used to make current selection visible

• expand_tabs: expand tabs to next 8 multiple column (to make configurable)

• number_lines: show line numbers

• regex: highlight a regex, takes 3 parameters <regex> <fg_color> <bg_color>

• group: highlighter group, containing other highlighters. takes one parameter, <group_name>. useful when multiple highlighters work together and need to be removed as one. Adding and removing from a group can be done using :addgrouphl <group> <highlighter_name> <highlighter_parameters…​> :rmgrouphl <group> <highlighter_name>

Filters

Filters can be installed to interact with buffer modifications. They can be added or removed with :addfilter <filter_name> <filter_parameters…​> and :rmfilter <filter_id>

exisiting filters are:

• preserve_indent: insert previous line indent when inserting a newline

• cleanup_whitespaces: remove trailing whitespaces on the previous line when inserting an end-of-line.

• expand_tabulations: insert spaces instead of tab characters

Hooks

commands can be registred to be executed when certain events arise. to register a hook, use the hook command.

:hook <scope> <hook_name> <filtering_regex> <command> <command_args>…​

<scope> can be either global or window, as hooks can be registered per window.

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

:hook global WinCreate .*\.cc addhl number_lines