KeyBindings

Key Bindings

Haskeline provides a line-editing user interface with many interactivity commands. Currently the user may choose either Emacs or Vi style bindings by editing the ~/.haskeline file; see UserPrefs for more details.

As of version 0.5, the user may specify custom key bindings in their .haskeline file.

Commands marked with (*) are available in version 0.6.2 and later. Commands marked with (**) are available in version 0.6.2.3 and later.

Definitions:

• ^A: Control-A
• M-A: Option-A
• [c]: Any Unicode printable character (Data.Char.isPrint returns True)
• [kill]: the console's 'kill' character (usually ^U)

Other input functions

Most of the below commands are only available in getInputLine. The other input functions provide a limited amount of interactivity:

• getInputChar returns as soon as the user types any printable character. It accepts the ^L (clear-screen) command.
• getPassword reads an obscured line of text from the user. It accepts the Backspace and ^L (clear-screen) commands.

Commands shared by both bindings

Key	Command
Left/right arrow	move the cursor left/right by one character
Return	finish the line entry
Backspace	delete the character left of the cursor
Delete	delete the character right of the cursor
[c]	insert a character
Up/down arrow	move backwards/forwards in the command history
Tab	run tab completion
^L	clear the screen
^R	search backwards in history
^S	search forwards in history
M-k	search backwards in history for a line matching the contents to the left of the cursor (*)
M-j	search forwards in history for a line matching the contents to the left of the cursor (*)
[kill]	delete until the start of the line

Emacs-specific bindings

Key	Command
^A	move to the start of the line
^E	move to the end of the line
^B	move left one character
^F	move right one char
^_ or ^X^U	undo
^D	delete the character to the right of the cursor
	^D is treated as an EOF if the input line is empty and the last character pressed was not also ^D.
M-F	move forwards one word
M-B	move backward one word
M-W	delete backwards one "big word"
M-Backspace	delete backwards one word
M-D	delete forwards one word
^K	delete until the end of the line
^N	move forwards in the history (*)
^P	move backwards in the history (*)
^Y	pop the most recent deletion off of the kill ring and paste it (*)
	Press ^Y multiple times to rotate through all saved deletions.
M-u	upper-case the next word (*)
M-l	lower-case the next word (*)
M-c	capitalize (first letter only) the current word (*)
^T	swap the character under the cursor with the previous one (*)
^Left	move backwards one word (**)
^Right	move forwards one word (**)

Vi-specific bindings

The Vi bindings start in "insert mode" allowing all of the shared commands listed above. If ^D is typed when the line is empty, it is treated as an EOF; otherwise, it is ignored. Pressing ESCAPE enters the "command mode" which provides all of the shared commands except for [printable char] and Tab, allowing instead the following commands:

Key	Command
i	enter insert mode
I	enter insert mode at the start of the line
a	enter insert mode after the current character
A	enter insert mode at end of the line
s	delete the char under the cursor and enter insert mode
S	clear the line and enter insert mode
r	replace one character
R	replace many characters
u	undo
^R	redo
[n][movement]	do a movement, repeated n times
[n]d[movement]	delete the characters the movement would move past
[n]c[movement]	delete the characters the movement would move past, and enter insert mode
[n]x	delete the character under the cursor (repeated n times)
[n]X	delete the character before the cursor (repeated n times) (*)
[n].	repeat the previous command n times (*)
dd	delete the whole line
cc	delete the whole line and enter insert mode
D	delete until the end of the line (*)
C	delete the rest of the line and enter insert mode (*)
j	previous line in the history (*)
k	next line in the history (*)
p	paste after the cursor (*)
P	paste before the cursor (*)
/	search backwards through the history (*)
?	search forwards through the history (*)
n	continue the current history search (*)
N	reverse the current history search (*)
~	toggle case (*)
^W	erase previous word (*)
^D	enter, when the line is not empty (*)

The movement commands are:

Key	Command
h	left one character
l	right one character
[space]	right one character
0	move to the start of the line
$	move to the end of the line
w	right one word
b	left one word
W	right one bigword
B	left one bigword
e	end of word (*)
E	end of bigword (*)
^	first non-whitespace character in the line (*)
f[c]	next appearance of character [c] (*)
F[c]	previous appearance of character [c] (*)
t[c]	to the left of the next appearance of character [c] (*)
T[c]	to the left of the previous appearance of character [c] (*)
%	jump to the brace matching the one under the cursor ((), {} or []) (*)