Arabic

Nvim :help pages, generated from source using the tree-sitter-vimdoc parser.

Arabic Language support (options & mappings) for Vim

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 WinSeparator 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 -- this also pertains to harakat and their combined forms). You can enable this option by entering

:set delcombine

in our VIM window. You can also append the 'delcombine' set command to your vimrc file. In other words, you can include ':set delcombine' to your vimrc file.

+ Arabic right-to-left Mode

By default VIM starts in Left-to-right mode. 'rightleft' is the command that allows one to alter a window's orientation - that can be accomplished via,

Toggling between left-to-right and right-to-left modes is accomplished through ':set rightleft' and ':set norightleft'.

While in Left-to-right mode, enter ':set rl' in the command line ('rl' is the abbreviation for rightleft).

Put the ':set rl' line in your vimrc file to start Vim in right-to-left mode permanently.

+ Arabic right-to-left command-line Mode

For certain commands the editing can be done in right-to-left mode. Currently this is only applicable to search commands.

This is controlled with the 'rightleftcmd' option. The default is "search", which means that windows in which 'rightleft' is set will edit search commands in right-left mode. To disable this behavior,

:set rightleftcmd=

To enable right-left editing of search commands again,

:set rightleftcmd&

+ Arabic Shaping Mode

To activate the required visual characters alterations (shaping, composing, combining) which the Arabic language requires, enable the 'arabicshape' command. This is done by entering

:set arabicshape

in our VIM window. You can also append the 'arabicshape' set command to your vimrc file. In other words, you can include ':set arabicshape' to your vimrc file.

Keymap/Keyboard arabickeymap

The character/letter encoding used in Vim is the standard UTF-8. It is widely discouraged that any other encoding be used or even attempted.

Note: UTF-8 is an all encompassing encoding and as such is the only supported (and encouraged) encoding with regard to Arabic (all other proprietary encodings should be discouraged and frowned upon).

o Keyboard

+ CTRL-^ in insert/replace mode toggles between Arabic/Latin mode

+ Keyboard mapping is based on the Microsoft's Arabic keymap (the de facto standard in the Arab world):

+---------------------------------------------------------------------+
|!   |@   |#   |$   |%   |^   |&   |*   |(   |)   |_   |+   ||   |~  ّ |
|1 ١ |2 ٢ |3 ٣ |4 ٤ |5 ٥ |6 ٦ |7 ٧ |8 ٨ |9 ٩ |0 ٠ |-   |=   |\   |` ذ |
+---------------------------------------------------------------------+
     |Q  َ |W  ً |E  ُ |R  ٌ |T لإ |Y إ |U ` |I ÷ |O x |P ؛ |{ < |} > |
     |q ض |w ص |e ث |r ق |t ف |y غ |u ع |i ه |o خ |p ح |[ ج |] د |
     +-----------------------------------------------------------+
       |A  ِ |S  ٍ |D [ |F ] |G لأ |H أ |J ـ |K ، |L / |:   |"   |
       |a ش |s س |d ي |f ب |g ل |h ا |j ت |k ن |l م |; ك |' ط |
       +------------------------------------------------------+
         |Z ~ |X  ْ |C { |V } |B لآ |N آ |M ' |< , |> . |? ؟ |
         |z ئ |x ء |c ؤ |v ر |b لا |n ى |m ة |, و |. ز |/ ظ |
         +-------------------------------------------------+

Restrictions

o Vim in its GUI form does not currently support Bi-directionality (i.e. the ability to see both Arabic and Latin intermixed within the same line).

Known Bugs

There is one known minor bug,

1. If you insert a haraka (e.g. Fatha (U+064E)) after a LAM (U+0644) and then insert an ALEF (U+0627), the appropriate combining will not happen due to the sandwiched haraka resulting in something that will NOT be displayed correctly.

WORK-AROUND: Don't include harakats between LAM and ALEF combos. In general, don't anticipate to see correct visual representation with regard to harakats and LAM+ALEF combined characters (even those entered after both characters). The problem noted is strictly a visual one, meaning saving such a file will contain all the appropriate info/encodings - nothing is lost.

No other bugs are known to exist.