Mercurial > vim
annotate runtime/doc/rileft.txt @ 21115:16f6b66cba21
Added tag v8.2.1108 for changeset d0265fdadec95a19f7bbbc34d78bd5faf32cd926
| author | Bram Moolenaar <Bram@vim.org> |
|---|---|
| date | Wed, 01 Jul 2020 16:00:06 +0200 |
| parents | af69c9335223 |
| children | 3a1ed539ae2a |
| rev | line source |
|---|---|
| 18879 | 1 *rileft.txt* For Vim version 8.2. Last change: 2019 May 05 |
| 7 | 2 |
| 3 | |
| 4 VIM REFERENCE MANUAL by Avner Lottem | |
| 5 updated by Nadim Shaikli | |
| 6 | |
| 7 | |
| 8 Right to Left display mode for Vim *rileft* | |
| 9 | |
| 10 | |
| 11 These functions were originally created by Avner Lottem: | |
| 12 E-mail: alottem@iil.intel.com | |
| 13 Phone: +972-4-8307322 | |
| 14 | |
| 15 *E26* | |
|
2570
71b56b4e7785
Make the references to features in the help more consistent. (Sylvain Hitier)
Bram Moolenaar <bram@vim.org>
parents:
2561
diff
changeset
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16 {only available when compiled with the |+rightleft| feature} |
| 7 | 17 |
| 18 | |
| 19 Introduction | |
| 20 ------------ | |
| 21 Some languages such as Arabic, Farsi, Hebrew (among others) require the | |
| 22 ability to display their text from right-to-left. Files in those languages | |
| 23 are stored conventionally and the right-to-left requirement is only a | |
| 24 function of the display engine (per the Unicode specification). In | |
| 25 right-to-left oriented files the characters appear on the screen from | |
| 26 right to left. | |
| 27 | |
| 28 Bidirectionality (or bidi for short) is what Unicode offers as a full | |
| 29 solution to these languages. Bidi offers the user the ability to view | |
| 30 both right-to-left as well as left-to-right text properly at the same time | |
| 31 within the same window. Vim currently, due to simplicity, does not offer | |
| 32 bidi and is merely opting to present a functional means to display/enter/use | |
| 33 right-to-left languages. An older hybrid solution in which direction is | |
| 34 encoded for every character (or group of characters) are not supported either | |
| 35 as this kind of support is out of the scope of a simple addition to an | |
| 236 | 36 existing editor (and it's not sanctioned by Unicode either). |
| 7 | 37 |
| 38 | |
| 39 Highlights | |
| 40 ---------- | |
| 41 o Editing left-to-right files as in the original Vim, no change. | |
| 42 | |
| 43 o Viewing and editing files in right-to-left windows. File orientation | |
| 44 is per window, so it is possible to view the same file in right-to-left | |
| 45 and left-to-right modes, simultaneously. (Useful for editing mixed files | |
| 46 in which both right-to-left and left-to-right text exist). | |
| 47 | |
| 48 o Compatibility to the original Vim. Almost all features work in | |
| 49 right-to-left mode (see Bugs below). | |
| 50 | |
| 51 o Backing from reverse insert mode to the correct place in the file | |
| 52 (if possible). | |
| 53 | |
| 54 o No special terminal with right-to-left capabilities is required. The | |
| 55 right-to-left changes are completely hardware independent. | |
| 56 | |
| 57 o Many languages use and require right-to-left support. These languages | |
| 58 can quite easily be supported given the inclusion of their required | |
| 59 keyboard mappings and some possible minor code change. Some of the | |
| 60 current supported languages include - |arabic.txt|, |farsi.txt| and | |
| 61 |hebrew.txt|. | |
| 62 | |
| 63 | |
| 64 Of Interest... | |
| 65 -------------- | |
| 66 | |
| 67 o Invocations | |
| 68 ----------- | |
| 69 + 'rightleft' ('rl') sets window orientation to right-to-left. | |
| 70 + 'delcombine' ('deco'), boolean, if editing UTF-8 encoded languages, | |
| 71 allows one to remove a composing character which gets superimposed | |
| 72 on those that proceeded them (some languages require this). | |
| 73 + 'rightleftcmd' ('rlc') sets the command-line within certain modes | |
| 74 (such as search) to be utilized in right-to-left orientation as well. | |
| 75 | |
| 76 o Typing backwards *ins-reverse* | |
| 77 ---------------- | |
| 78 In lieu of using full-fledged the 'rightleft' option, one can opt for | |
| 79 reverse insertion. When the 'revins' (reverse insert) option is set, | |
| 80 inserting happens backwards. This can be used to type right-to-left | |
| 81 text. When inserting characters the cursor is not moved and the text | |
| 82 moves rightwards. A <BS> deletes the character under the cursor. | |
| 83 CTRL-W and CTRL-U also work in the opposite direction. <BS>, CTRL-W | |
| 84 and CTRL-U do not stop at the start of insert or end of line, no matter | |
| 85 how the 'backspace' option is set. | |
| 86 | |
| 87 There is no reverse replace mode (yet). | |
| 88 | |
| 89 If the 'showmode' option is set, "-- REVERSE INSERT --" will be shown | |
| 90 in the status line when reverse Insert mode is active. | |
| 91 | |
| 92 o Pasting when in a rightleft window | |
| 93 ---------------------------------- | |
| 94 When cutting text with the mouse and pasting it in a rightleft window | |
| 95 the text will be reversed, because the characters come from the cut buffer | |
| 96 from the left to the right, while inserted in the file from the right to | |
| 97 the left. In order to avoid it, toggle 'revins' before pasting. | |
| 98 | |
| 99 | |
| 100 Bugs | |
| 101 ---- | |
| 102 o Does not handle CTRL-A and CTRL-X commands (add and subtract) correctly | |
| 103 when in rightleft window. | |
| 104 | |
| 105 o Does not support reverse insert and rightleft modes on the command-line. | |
| 106 However, functionality of the editor is not reduced, because it is | |
| 107 possible to enter mappings, abbreviations and searches typed from the | |
| 108 left to the right on the command-line. | |
| 109 | |
| 110 o Somewhat slower in right-to-left mode, because right-to-left motion is | |
| 111 emulated inside Vim, not by the controlling terminal. | |
| 112 | |
| 113 o When the Athena GUI is used, the bottom scrollbar works in the wrong | |
| 114 direction. This is difficult to fix. | |
| 115 | |
| 116 o When both 'rightleft' and 'revins' are on: 'textwidth' does not work. | |
| 117 Lines do not wrap at all; you just get a single, long line. | |
| 118 | |
| 119 o There is no full bidirectionality (bidi) support. | |
| 120 | |
| 121 | |
| 14421 | 122 vim:tw=78:ts=8:noet:ft=help:norl: |