Vim documentation: arabic
main help file
*arabic.txt* For Vim version 9.0. Last change: 2021 Jun 22
VIM REFERENCE MANUAL by Nadim Shaikli
Arabic Language support (options & mappings) for Vim *Arabic*
*E800*
In order to use right-to-left and Arabic mapping support, it is
necessary to compile Vim with the |+arabic| feature.
These functions have been created by Nadim Shaikli <nadim-at-arabeyes.org>
It is best to view this file with these settings within Vim's GUI:
:set encoding=utf-8
:set arabicshape
Introduction
Arabic is a rather demanding language in which a number of special
features are required. Characters are right-to-left oriented and
ought to appear as such on the screen (i.e. from right to left).
Arabic also requires shaping of its characters, meaning the same
character has a different visual form based on its relative location
within a word (initial, medial, final or stand-alone). Arabic also
requires two different forms of combining and the ability, in
certain instances, to either superimpose up to two characters on top
of another (composing) or the actual substitution of two characters
into one (combining). Lastly, to display Arabic properly one will
require not only ISO-8859-6 (U+0600-U+06FF) fonts, but will also
require Presentation Form-B (U+FE70-U+FEFF) fonts both of which are
subsets within a so-called ISO-10646-1 font.
The commands, prompts and help files are not in Arabic, therefore
the user interface remains the standard Vi interface.
Highlights
o Editing left-to-right files as in the original Vim hasn't changed.
o Viewing and editing files in right-to-left windows. File
orientation is per window, so it is possible to view the same
file in right-to-left and left-to-right modes, simultaneously.
o No special terminal with right-to-left capabilities is required.
The right-to-left changes are completely hardware independent.
Only Arabic fonts are necessary.
o Compatible with the original Vim. Almost all features work in
right-to-left mode (there are liable to be bugs).
o Changing keyboard mapping and reverse insert modes using a single
command.
o Toggling complete Arabic support via a single command.
o While in Arabic mode, numbers are entered from left to right. Upon
entering a none number character, that character will be inserted
just into the left of the last number.
o Arabic keymapping on the command line in reverse insert mode.
o Proper Bidirectional functionality is possible given Vim is
started within a Bidi capable terminal emulator.
Arabic Fonts *arabicfonts*
Vim requires monospaced fonts of which there are many out there.
Arabic requires ISO-8859-6 as well as Presentation Form-B fonts
(without Form-B, Arabic will _NOT_ be usable). It is highly
recommended that users search for so-called 'ISO-10646-1' fonts.
Do an Internet search or check www.arabeyes.org for further
info on where to obtain the necessary Arabic fonts.
Font Installation
o Installation of fonts for X Window systems (Unix/Linux)
Depending on your system, copy your_ARABIC_FONT file into a
directory of your choice. Change to the directory containing
the Arabic fonts and execute the following commands:
% mkfontdir
% xset +fp path_name_of_arabic_fonts_directory
Usage
Prior to the actual usage of Arabic within Vim, a number of settings
need to be accounted for and invoked.
o Setting the Arabic fonts
+ For Vim GUI set the 'guifont' to your_ARABIC_FONT. This is done
by entering the following command in the Vim window.
:set guifont=your_ARABIC_FONT
NOTE: the string 'your_ARABIC_FONT' is used to denote a complete
font name akin to that used in Linux/Unix systems.
(e.g. -misc-fixed-medium-r-normal--20-200-75-75-c-100-iso10646-1)
You can append the 'guifont' set command to your .vimrc file
in order to get the same above noted results. In other words,
you can include ':set guifont=your_ARABIC_FONT' to your .vimrc
file.
+ Under the X Window environment, you can also start Vim with
'-fn your_ARABIC_FONT' option.
o Setting the appropriate character Encoding
To enable the correct Arabic encoding the following command needs
to be appended,
:set encoding=utf-8
to your .vimrc file (entering the command manually into your Vim
window is highly discouraged). In short, include ':set
encoding=utf-8' to your .vimrc file.
Attempts to use Arabic without UTF-8 will result the following
warning message,
*W17*
Arabic requires UTF-8, do ':set encoding=utf-8'
o Enable Arabic settings [short-cut]
In order to simplify and streamline things, you can either invoke
Vim with the command-line option,
% vim -A my_utf8_arabic_file ...
or enable 'arabic' via the following command within Vim
:set arabic
The two above noted possible invocations are the preferred manner
in which users are instructed to proceed. Barring an enabled 'termbidi'
setting, both command options:
1. set the appropriate keymap
2. enable the deletion of a single combined pair character
3. enable rightleft mode
4. enable rightleftcmd mode (affecting the command-line)
5. enable arabicshape mode (do visual character alterations)
You may also append the command to your .vimrc file and simply
include ':set arabic' to it.
You are also capable of disabling Arabic support via
:set noarabic
which resets everything that the command had enabled without touching
the global settings as they could affect other possible open buffers.
In short the 'noarabic' command,
1. resets to the alternate keymap
2. disables the deletion of a single combined pair character
3. disables rightleft mode
NOTE: the 'arabic' command takes into consideration 'termbidi' for
possible external bi-directional (bidi) support from the
terminal ("mlterm" for instance offers such support).
'termbidi', if available, is superior to rightleft support
and its support is preferred due to its level of offerings.
'arabic' when 'termbidi' is enabled only sets the keymap.
For vertical window isolation while setting 'termbidi' an LTR
vertical separator like "l" or "𝖨" may be used. It may also be
hidden by changing its color to the foreground color:
:set fillchars=vert:l
:hi VertSplit ctermbg=White
Note that this is a workaround, not a proper solution.
If, on the other hand, you'd like to be verbose and explicit and
are opting not to use the 'arabic' short-cut command, here's what
is needed (i.e. if you use ':set arabic' you can skip this section) -
+ Arabic Keymapping Activation
To activate the Arabic keymap (i.e. to remap your English/Latin
keyboard to look-n-feel like a standard Arabic one), set the
'keymap' command to "arabic". This is done by entering
:set keymap=arabic
in your Vim window. You can also append the 'keymap' set command to
your .vimrc file. In other words, you can include ':set keymap=arabic'
to your .vimrc file.
To turn toggle (or switch) your keymapping between Arabic and the
default mapping (English), it is advised that users use the 'CTRL-^'
key press while in insert (or add/replace) mode. The command-line
will display your current mapping by displaying an "Arabic" string
next to your insertion mode (e.g. -- INSERT Arabic --) indicating
your current keymap.
+ Arabic deletion of a combined pair character
By default Vim has the 'delcombine' option disabled. This option
allows the deletion of ALEF in a LAM_ALEF (LAA) combined character
and still retain the LAM (i.e. it reverts to treating the combined
character as its natural two characters form --