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It is worth preserving, but let it live in spell.txt so we can dedicate develop.txt to nvim-specific discussion.
1740 lines
67 KiB
Plaintext
1740 lines
67 KiB
Plaintext
*spell.txt*
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VIM REFERENCE MANUAL by Bram Moolenaar
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Spell checking *spell*
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1. Quick start |spell-quickstart|
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2. Remarks on spell checking |spell-remarks|
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3. Generating a spell file |spell-mkspell|
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4. Spell file format |spell-file-format|
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==============================================================================
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1. Quick start *spell-quickstart* *E756*
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This command switches on spell checking: >
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:setlocal spell spelllang=en_us
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This switches on the 'spell' option and specifies to check for US English.
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The words that are not recognized are highlighted with one of these:
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SpellBad word not recognized |hl-SpellBad|
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SpellCap word not capitalised |hl-SpellCap|
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SpellRare rare word |hl-SpellRare|
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SpellLocal wrong spelling for selected region |hl-SpellLocal|
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Vim only checks words for spelling, there is no grammar check.
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If the 'mousemodel' option is set to "popup" and the cursor is on a badly
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spelled word or it is "popup_setpos" and the mouse pointer is on a badly
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spelled word, then the popup menu will contain a submenu to replace the bad
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word. Note: this slows down the appearance of the popup menu.
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To search for the next misspelled word:
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*]s*
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]s Move to next misspelled word after the cursor.
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A count before the command can be used to repeat.
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'wrapscan' applies.
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*[s*
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[s Like "]s" but search backwards, find the misspelled
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word before the cursor. Doesn't recognize words
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split over two lines, thus may stop at words that are
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not highlighted as bad. Does not stop at word with
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missing capital at the start of a line.
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*]S*
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]S Like "]s" but only stop at bad words, not at rare
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words or words for another region.
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*[S*
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[S Like "]S" but search backwards.
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To add words to your own word list:
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*zg*
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zg Add word under the cursor as a good word to the first
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name in 'spellfile'. A count may precede the command
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to indicate the entry in 'spellfile' to be used. A
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count of two uses the second entry.
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In Visual mode the selected characters are added as a
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word (including white space!).
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When the cursor is on text that is marked as badly
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spelled then the marked text is used.
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Otherwise the word under the cursor, separated by
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non-word characters, is used.
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If the word is explicitly marked as bad word in
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another spell file the result is unpredictable.
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*zG*
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zG Like "zg" but add the word to the internal word list
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|internal-wordlist|.
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*zw*
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zw Like "zg" but mark the word as a wrong (bad) word.
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If the word already appears in 'spellfile' it is
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turned into a comment line. See |spellfile-cleanup|
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for getting rid of those.
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*zW*
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zW Like "zw" but add the word to the internal word list
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|internal-wordlist|.
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zuw *zug* *zuw*
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zug Undo |zw| and |zg|, remove the word from the entry in
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'spellfile'. Count used as with |zg|.
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zuW *zuG* *zuW*
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zuG Undo |zW| and |zG|, remove the word from the internal
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word list. Count used as with |zg|.
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*:spe* *:spellgood*
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:[count]spe[llgood] {word}
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Add {word} as a good word to 'spellfile', like with
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|zg|. Without count the first name is used, with a
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count of two the second entry, etc.
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:spe[llgood]! {word} Add {word} as a good word to the internal word list,
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like with |zG|.
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*:spellw* *:spellwrong*
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:[count]spellw[rong] {word}
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Add {word} as a wrong (bad) word to 'spellfile', as
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with |zw|. Without count the first name is used, with
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a count of two the second entry, etc.
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:spellw[rong]! {word} Add {word} as a wrong (bad) word to the internal word
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list, like with |zW|.
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:[count]spellu[ndo] {word} *:spellu* *:spellundo*
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Like |zuw|. [count] used as with |:spellgood|.
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:spellu[ndo]! {word} Like |zuW|. [count] used as with |:spellgood|.
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After adding a word to 'spellfile' with the above commands its associated
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".spl" file will automatically be updated and reloaded. If you change
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'spellfile' manually you need to use the |:mkspell| command. This sequence of
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commands mostly works well: >
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:edit <file in 'spellfile'>
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< (make changes to the spell file) >
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:mkspell! %
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More details about the 'spellfile' format below |spell-wordlist-format|.
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*internal-wordlist*
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The internal word list is used for all buffers where 'spell' is set. It is
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not stored, it is lost when you exit Vim. It is also cleared when 'encoding'
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is set.
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Finding suggestions for bad words:
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*z=*
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z= For the word under/after the cursor suggest correctly
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spelled words. This also works to find alternatives
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for a word that is not highlighted as a bad word,
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e.g., when the word after it is bad.
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In Visual mode the highlighted text is taken as the
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word to be replaced.
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The results are sorted on similarity to the word being
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replaced.
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This may take a long time. Hit CTRL-C when you get
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bored.
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If the command is used without a count the
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alternatives are listed and you can enter the number
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of your choice or press <Enter> if you don't want to
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replace. You can also use the mouse to click on your
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choice (only works if the mouse can be used in Normal
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mode and when there are no line wraps). Click on the
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first line (the header) to cancel.
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The suggestions listed normally replace a highlighted
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bad word. Sometimes they include other text, in that
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case the replaced text is also listed after a "<".
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If a count is used that suggestion is used, without
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prompting. For example, "1z=" always takes the first
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suggestion.
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If 'verbose' is non-zero a score will be displayed
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with the suggestions to indicate the likeliness to the
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badly spelled word (the higher the score the more
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different).
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When a word was replaced the redo command "." will
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repeat the word replacement. This works like "ciw",
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the good word and <Esc>. This does NOT work for Thai
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and other languages without spaces between words.
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*:spellr* *:spellrepall* *E752* *E753*
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:spellr[epall] Repeat the replacement done by |z=| for all matches
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with the replaced word in the current window.
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In Insert mode, when the cursor is after a badly spelled word, you can use
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CTRL-X s to find suggestions. This works like Insert mode completion. Use
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CTRL-N to use the next suggestion, CTRL-P to go back. |i_CTRL-X_s|
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The 'spellsuggest' option influences how the list of suggestions is generated
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and sorted. See |'spellsuggest'|.
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The 'spellcapcheck' option is used to check the first word of a sentence
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starts with a capital. This doesn't work for the first word in the file.
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When there is a line break right after a sentence the highlighting of the next
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line may be postponed. Use |CTRL-L| when needed. Also see |set-spc-auto| for
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how it can be set automatically when 'spelllang' is set.
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Vim counts the number of times a good word is encountered. This is used to
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sort the suggestions: words that have been seen before get a small bonus,
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words that have been seen often get a bigger bonus. The COMMON item in the
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affix file can be used to define common words, so that this mechanism also
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works in a new or short file |spell-COMMON|.
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==============================================================================
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2. Remarks on spell checking *spell-remarks*
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PERFORMANCE
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Vim does on-the-fly spell checking. To make this work fast the word list is
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loaded in memory. Thus this uses a lot of memory (1 Mbyte or more). There
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might also be a noticeable delay when the word list is loaded, which happens
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when 'spell' is set and when 'spelllang' is set while 'spell' was already set.
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To minimize the delay each word list is only loaded once, it is not deleted
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when 'spelllang' is made empty or 'spell' is reset. When 'encoding' is set
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all the word lists are reloaded, thus you may notice a delay then too.
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REGIONS
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A word may be spelled differently in various regions. For example, English
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comes in (at least) these variants:
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en all regions
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en_au Australia
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en_ca Canada
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en_gb Great Britain
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en_nz New Zealand
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en_us USA
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Words that are not used in one region but are used in another region are
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highlighted with SpellLocal |hl-SpellLocal|.
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Always use lowercase letters for the language and region names.
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When adding a word with |zg| or another command it's always added for all
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regions. You can change that by manually editing the 'spellfile'. See
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|spell-wordlist-format|. Note that the regions as specified in the files in
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'spellfile' are only used when all entries in 'spelllang' specify the same
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region (not counting files specified by their .spl name).
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*spell-german*
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Specific exception: For German these special regions are used:
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de all German words accepted
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de_de old and new spelling
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de_19 old spelling
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de_20 new spelling
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de_at Austria
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de_ch Switzerland
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*spell-russian*
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Specific exception: For Russian these special regions are used:
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ru all Russian words accepted
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ru_ru "IE" letter spelling
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ru_yo "YO" letter spelling
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*spell-yiddish*
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Yiddish requires using "utf-8" encoding, because of the special characters
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used. If you are using latin1 Vim will use transliterated (romanized) Yiddish
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instead. If you want to use transliterated Yiddish with utf-8 use "yi-tr".
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In a table:
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'encoding' 'spelllang'
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utf-8 yi Yiddish
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latin1 yi transliterated Yiddish
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utf-8 yi-tr transliterated Yiddish
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*spell-cjk*
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Chinese, Japanese and other East Asian characters are normally marked as
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errors, because spell checking of these characters is not supported. If
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'spelllang' includes "cjk", these characters are not marked as errors. This
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is useful when editing text with spell checking while some Asian words are
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present.
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SPELL FILES *spell-load*
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Vim searches for spell files in the "spell" subdirectory of the directories in
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'runtimepath'. The name is: LL.EEE.spl, where:
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LL the language name
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EEE the value of 'encoding'
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The value for "LL" comes from 'spelllang', but excludes the region name.
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Examples:
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'spelllang' LL ~
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en_us en
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en-rare en-rare
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medical_ca medical
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Only the first file is loaded, the one that is first in 'runtimepath'. If
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this succeeds then additionally files with the name LL.EEE.add.spl are loaded.
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All the ones that are found are used.
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If no spell file is found the |SpellFileMissing| autocommand event is
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triggered. This may trigger the |spellfile.vim| plugin to offer you
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downloading the spell file.
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Additionally, the files related to the names in 'spellfile' are loaded. These
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are the files that |zg| and |zw| add good and wrong words to.
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Exceptions:
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- Vim uses "latin1" when 'encoding' is "iso-8859-15". The euro sign doesn't
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matter for spelling.
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- When no spell file for 'encoding' is found "ascii" is tried. This only
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works for languages where nearly all words are ASCII, such as English. It
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helps when 'encoding' is not "latin1", such as iso-8859-2, and English text
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is being edited. For the ".add" files the same name as the found main
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spell file is used.
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For example, with these values:
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'runtimepath' is "~/.config/nvim,/usr/share/vim70,~/.config/nvim/after"
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'encoding' is "iso-8859-2"
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'spelllang' is "pl"
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Vim will look for:
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1. ~/.config/nvim/spell/pl.iso-8859-2.spl
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2. /usr/share/vim70/spell/pl.iso-8859-2.spl
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3. ~/.config/nvim/spell/pl.iso-8859-2.add.spl
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4. /usr/share/vim70/spell/pl.iso-8859-2.add.spl
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5. ~/.config/nvim/after/spell/pl.iso-8859-2.add.spl
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This assumes 1. is not found and 2. is found.
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If 'encoding' is "latin1" Vim will look for:
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1. ~/.config/nvim/spell/pl.latin1.spl
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2. /usr/share/vim70/spell/pl.latin1.spl
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3. ~/.config/nvim/after/spell/pl.latin1.spl
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4. ~/.config/nvim/spell/pl.ascii.spl
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5. /usr/share/vim70/spell/pl.ascii.spl
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6. ~/.config/nvim/after/spell/pl.ascii.spl
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This assumes none of them are found (Polish doesn't make sense when leaving
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out the non-ASCII characters).
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A spell file might not be available in the current 'encoding'. See
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|spell-mkspell| about how to create a spell file. Converting a spell file
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with "iconv" will NOT work!
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*spell-sug-file* *E781*
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If there is a file with exactly the same name as the ".spl" file but ending in
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".sug", that file will be used for giving better suggestions. It isn't loaded
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before suggestions are made to reduce memory use.
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*E758* *E759* *E778* *E779* *E780* *E782*
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When loading a spell file Vim checks that it is properly formatted. If you
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get an error the file may be truncated, modified or intended for another Vim
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version.
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SPELLFILE CLEANUP *spellfile-cleanup*
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The |zw| command turns existing entries in 'spellfile' into comment lines.
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This avoids having to write a new file every time, but results in the file
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only getting longer, never shorter. To clean up the comment lines in all
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".add" spell files do this: >
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:runtime spell/cleanadd.vim
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This deletes all comment lines, except the ones that start with "##". Use
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"##" lines to add comments that you want to keep.
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You can invoke this script as often as you like. A variable is provided to
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skip updating files that have been changed recently. Set it to the number of
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seconds that has passed since a file was changed before it will be cleaned.
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For example, to clean only files that were not changed in the last hour: >
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let g:spell_clean_limit = 60 * 60
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The default is one second.
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WORDS
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Vim uses a fixed method to recognize a word. This is independent of
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'iskeyword', so that it also works in help files and for languages that
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include characters like '-' in 'iskeyword'. The word characters do depend on
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'encoding'.
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The table with word characters is stored in the main .spl file. Therefore it
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matters what the current locale is when generating it! A .add.spl file does
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not contain a word table though.
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For a word that starts with a digit the digit is ignored, unless the word as a
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whole is recognized. Thus if "3D" is a word and "D" is not then "3D" is
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recognized as a word, but if "3D" is not a word then only the "D" is marked as
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bad. Hex numbers in the form 0x12ab and 0X12AB are recognized.
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WORD COMBINATIONS
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It is possible to spell-check words that include a space. This is used to
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recognize words that are invalid when used by themselves, e.g. for "et al.".
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It can also be used to recognize "the the" and highlight it.
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The number of spaces is irrelevant. In most cases a line break may also
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appear. However, this makes it difficult to find out where to start checking
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for spelling mistakes. When you make a change to one line and only that line
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is redrawn Vim won't look in the previous line, thus when "et" is at the end
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of the previous line "al." will be flagged as an error. And when you type
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"the<CR>the" the highlighting doesn't appear until the first line is redrawn.
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Use |CTRL-L| to redraw right away. "[s" will also stop at a word combination
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with a line break.
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When encountering a line break Vim skips characters such as '*', '>' and '"',
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so that comments in C, shell and Vim code can be spell checked.
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SYNTAX HIGHLIGHTING *spell-syntax*
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Files that use syntax highlighting can specify where spell checking should be
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done:
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1. everywhere default
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2. in specific items use "contains=@Spell"
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3. everywhere but specific items use "contains=@NoSpell"
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For the second method adding the @NoSpell cluster will disable spell checking
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again. This can be used, for example, to add @Spell to the comments of a
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program, and add @NoSpell for items that shouldn't be checked.
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Also see |:syn-spell| for text that is not in a syntax item.
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VIM SCRIPTS
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If you want to write a Vim script that does something with spelling, you may
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find these functions useful:
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spellbadword() find badly spelled word at the cursor
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spellsuggest() get list of spelling suggestions
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soundfold() get the sound-a-like version of a word
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SETTING 'spellcapcheck' AUTOMATICALLY *set-spc-auto*
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After the 'spelllang' option has been set successfully, Vim will source the
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files "spell/LANG.vim" in 'runtimepath'. "LANG" is the value of 'spelllang'
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up to the first comma, dot or underscore. This can be used to set options
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specifically for the language, especially 'spellcapcheck'.
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The distribution includes a few of these files. Use this command to see what
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they do: >
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:next $VIMRUNTIME/spell/*.vim
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Note that the default scripts don't set 'spellcapcheck' if it was changed from
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the default value. This assumes the user prefers another value then.
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DOUBLE SCORING *spell-double-scoring*
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The 'spellsuggest' option can be used to select "double" scoring. This
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mechanism is based on the principle that there are two kinds of spelling
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mistakes:
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1. You know how to spell the word, but mistype something. This results in a
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small editing distance (character swapped/omitted/inserted) and possibly a
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word that sounds completely different.
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2. You don't know how to spell the word and type something that sounds right.
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The edit distance can be big but the word is similar after sound-folding.
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Since scores for these two mistakes will be very different we use a list
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for each and mix them.
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The sound-folding is slow and people that know the language won't make the
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second kind of mistakes. Therefore 'spellsuggest' can be set to select the
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preferred method for scoring the suggestions.
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==============================================================================
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3. Generating a spell file *spell-mkspell*
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Vim uses a binary file format for spelling. This greatly speeds up loading
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the word list and keeps it small.
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*.aff* *.dic* *Myspell*
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You can create a Vim spell file from the .aff and .dic files that Myspell
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uses. Myspell is used by OpenOffice.org and Mozilla. The OpenOffice .oxt
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files are zip files which contain the .aff and .dic files. You should be able
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to find them here:
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http://extensions.services.openoffice.org/dictionary
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The older, OpenOffice 2 files may be used if this doesn't work:
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http://wiki.services.openoffice.org/wiki/Dictionaries
|
||
You can also use a plain word list. The results are the same, the choice
|
||
depends on what word lists you can find.
|
||
|
||
If you install Aap (from www.a-a-p.org) you can use the recipes in the
|
||
runtime/spell/??/ directories. Aap will take care of downloading the files,
|
||
apply patches needed for Vim and build the .spl file.
|
||
|
||
Make sure your current locale is set properly, otherwise Vim doesn't know what
|
||
characters are upper/lower case letters. If the locale isn't available (e.g.,
|
||
when using an MS-Windows codepage on Unix) add tables to the .aff file
|
||
|spell-affix-chars|. If the .aff file doesn't define a table then the word
|
||
table of the currently active spelling is used. If spelling is not active
|
||
then Vim will try to guess.
|
||
|
||
*:mksp* *:mkspell*
|
||
:mksp[ell][!] [-ascii] {outname} {inname} ...
|
||
Generate a Vim spell file from word lists. Example: >
|
||
:mkspell /tmp/nl nl_NL.words
|
||
< *E751*
|
||
When {outname} ends in ".spl" it is used as the output
|
||
file name. Otherwise it should be a language name,
|
||
such as "en", without the region name. The file
|
||
written will be "{outname}.{encoding}.spl", where
|
||
{encoding} is the value of the 'encoding' option.
|
||
|
||
When the output file already exists [!] must be used
|
||
to overwrite it.
|
||
|
||
When the [-ascii] argument is present, words with
|
||
non-ascii characters are skipped. The resulting file
|
||
ends in "ascii.spl".
|
||
|
||
The input can be the Myspell format files {inname}.aff
|
||
and {inname}.dic. If {inname}.aff does not exist then
|
||
{inname} is used as the file name of a plain word
|
||
list.
|
||
|
||
Multiple {inname} arguments can be given to combine
|
||
regions into one Vim spell file. Example: >
|
||
:mkspell ~/.vim/spell/en /tmp/en_US /tmp/en_CA /tmp/en_AU
|
||
< This combines the English word lists for US, CA and AU
|
||
into one en.spl file.
|
||
Up to eight regions can be combined. *E754* *E755*
|
||
The REP and SAL items of the first .aff file where
|
||
they appear are used. |spell-REP| |spell-SAL|
|
||
*E845*
|
||
This command uses a lot of memory, required to find
|
||
the optimal word tree (Polish, Italian and Hungarian
|
||
require several hundred Mbyte). The final result will
|
||
be much smaller, because compression is used. To
|
||
avoid running out of memory compression will be done
|
||
now and then. This can be tuned with the 'mkspellmem'
|
||
option.
|
||
|
||
After the spell file was written and it was being used
|
||
in a buffer it will be reloaded automatically.
|
||
|
||
:mksp[ell] [-ascii] {name}.{enc}.add
|
||
Like ":mkspell" above, using {name}.{enc}.add as the
|
||
input file and producing an output file in the same
|
||
directory that has ".spl" appended.
|
||
|
||
:mksp[ell] [-ascii] {name}
|
||
Like ":mkspell" above, using {name} as the input file
|
||
and producing an output file in the same directory
|
||
that has ".{enc}.spl" appended.
|
||
|
||
Vim will report the number of duplicate words. This might be a mistake in the
|
||
list of words. But sometimes it is used to have different prefixes and
|
||
suffixes for the same basic word to avoid them combining (e.g. Czech uses
|
||
this). If you want Vim to report all duplicate words set the 'verbose'
|
||
option.
|
||
|
||
Since you might want to change a Myspell word list for use with Vim the
|
||
following procedure is recommended:
|
||
|
||
1. Obtain the xx_YY.aff and xx_YY.dic files from Myspell.
|
||
2. Make a copy of these files to xx_YY.orig.aff and xx_YY.orig.dic.
|
||
3. Change the xx_YY.aff and xx_YY.dic files to remove bad words, add missing
|
||
words, define word characters with FOL/LOW/UPP, etc. The distributed
|
||
"*.diff" files can be used.
|
||
4. Start Vim with the right locale and use |:mkspell| to generate the Vim
|
||
spell file.
|
||
5. Try out the spell file with ":set spell spelllang=xx" if you wrote it in
|
||
a spell directory in 'runtimepath', or ":set spelllang=xx.enc.spl" if you
|
||
wrote it somewhere else.
|
||
|
||
When the Myspell files are updated you can merge the differences:
|
||
1. Obtain the new Myspell files as xx_YY.new.aff and xx_UU.new.dic.
|
||
2. Use |diff-mode| to see what changed: >
|
||
nvim -d xx_YY.orig.dic xx_YY.new.dic
|
||
3. Take over the changes you like in xx_YY.dic.
|
||
You may also need to change xx_YY.aff.
|
||
4. Rename xx_YY.new.dic to xx_YY.orig.dic and xx_YY.new.aff to xx_YY.new.aff.
|
||
|
||
|
||
SPELL FILE VERSIONS *E770* *E771* *E772*
|
||
|
||
Spell checking is a relatively new feature in Vim, thus it's possible that the
|
||
.spl file format will be changed to support more languages. Vim will check
|
||
the validity of the spell file and report anything wrong.
|
||
|
||
E771: Old spell file, needs to be updated ~
|
||
This spell file is older than your Vim. You need to update the .spl file.
|
||
|
||
E772: Spell file is for newer version of Vim ~
|
||
This means the spell file was made for a later version of Vim. You need to
|
||
update Vim.
|
||
|
||
E770: Unsupported section in spell file ~
|
||
This means the spell file was made for a later version of Vim and contains a
|
||
section that is required for the spell file to work. In this case it's
|
||
probably a good idea to upgrade your Vim.
|
||
|
||
|
||
SPELL FILE DUMP
|
||
|
||
If for some reason you want to check what words are supported by the currently
|
||
used spelling files, use this command:
|
||
|
||
*:spelldump* *:spelld*
|
||
:spelld[ump] Open a new window and fill it with all currently valid
|
||
words. Compound words are not included.
|
||
Note: For some languages the result may be enormous,
|
||
causing Vim to run out of memory.
|
||
|
||
:spelld[ump]! Like ":spelldump" and include the word count. This is
|
||
the number of times the word was found while
|
||
updating the screen. Words that are in COMMON items
|
||
get a starting count of 10.
|
||
|
||
The format of the word list is used |spell-wordlist-format|. You should be
|
||
able to read it with ":mkspell" to generate one .spl file that includes all
|
||
the words.
|
||
|
||
When all entries to 'spelllang' use the same regions or no regions at all then
|
||
the region information is included in the dumped words. Otherwise only words
|
||
for the current region are included and no "/regions" line is generated.
|
||
|
||
Comment lines with the name of the .spl file are used as a header above the
|
||
words that were generated from that .spl file.
|
||
|
||
|
||
SPELL FILE MISSING *spell-SpellFileMissing* *spellfile.vim*
|
||
|
||
If the spell file for the language you are using is not available, you will
|
||
get an error message. But if the "spellfile.vim" plugin is active it will
|
||
offer you to download the spell file. Just follow the instructions, it will
|
||
ask you where to write the file (there must be a writable directory in
|
||
'runtimepath' for this).
|
||
|
||
The plugin has a default place where to look for spell files, on the Vim ftp
|
||
server. If you want to use another location or another protocol, set the
|
||
g:spellfile_URL variable to the directory that holds the spell files. The
|
||
|netrw| plugin is used for getting the file, look there for the specific
|
||
syntax of the URL. Example: >
|
||
let g:spellfile_URL = 'http://ftp.vim.org/vim/runtime/spell'
|
||
You may need to escape special characters.
|
||
|
||
The plugin will only ask about downloading a language once. If you want to
|
||
try again anyway restart Vim, or set g:spellfile_URL to another value (e.g.,
|
||
prepend a space).
|
||
|
||
To avoid using the "spellfile.vim" plugin do this in your vimrc file: >
|
||
|
||
let loaded_spellfile_plugin = 1
|
||
|
||
Instead of using the plugin you can define a |SpellFileMissing| autocommand to
|
||
handle the missing file yourself. You can use it like this: >
|
||
|
||
:au SpellFileMissing * call Download_spell_file(expand('<amatch>'))
|
||
|
||
Thus the <amatch> item contains the name of the language. Another important
|
||
value is 'encoding', since every encoding has its own spell file. With two
|
||
exceptions:
|
||
- For ISO-8859-15 (latin9) the name "latin1" is used (the encodings only
|
||
differ in characters not used in dictionary words).
|
||
- The name "ascii" may also be used for some languages where the words use
|
||
only ASCII letters for most of the words.
|
||
|
||
The default "spellfile.vim" plugin uses this autocommand, if you define your
|
||
autocommand afterwards you may want to use ":au! SpellFileMissing" to overrule
|
||
it. If you define your autocommand before the plugin is loaded it will notice
|
||
this and not do anything.
|
||
*E797*
|
||
Note that the SpellFileMissing autocommand must not change or destroy the
|
||
buffer the user was editing.
|
||
|
||
==============================================================================
|
||
4. Spell file format *spell-file-format*
|
||
|
||
This is the format of the files that are used by the person who creates and
|
||
maintains a word list.
|
||
|
||
Note that we avoid the word "dictionary" here. That is because the goal of
|
||
spell checking differs from writing a dictionary (as in the book). For
|
||
spelling we need a list of words that are OK, thus should not be highlighted.
|
||
Person and company names will not appear in a dictionary, but do appear in a
|
||
word list. And some old words are rarely used while they are common
|
||
misspellings. These do appear in a dictionary but not in a word list.
|
||
|
||
There are two formats: A straight list of words and a list using affix
|
||
compression. The files with affix compression are used by Myspell (Mozilla
|
||
and OpenOffice.org). This requires two files, one with .aff and one with .dic
|
||
extension.
|
||
|
||
|
||
FORMAT OF STRAIGHT WORD LIST *spell-wordlist-format*
|
||
|
||
The words must appear one per line. That is all that is required.
|
||
|
||
Additionally the following items are recognized:
|
||
|
||
- Empty and blank lines are ignored.
|
||
|
||
# comment ~
|
||
- Lines starting with a # are ignored (comment lines).
|
||
|
||
/encoding=utf-8 ~
|
||
- A line starting with "/encoding=", before any word, specifies the encoding
|
||
of the file. After the second '=' comes an encoding name. This tells Vim
|
||
to setup conversion from the specified encoding to 'encoding'. Thus you can
|
||
use one word list for several target encodings.
|
||
|
||
/regions=usca ~
|
||
- A line starting with "/regions=" specifies the region names that are
|
||
supported. Each region name must be two ASCII letters. The first one is
|
||
region 1. Thus "/regions=usca" has region 1 "us" and region 2 "ca".
|
||
In an addition word list the region names should be equal to the main word
|
||
list!
|
||
|
||
- Other lines starting with '/' are reserved for future use. The ones that
|
||
are not recognized are ignored. You do get a warning message, so that you
|
||
know something won't work.
|
||
|
||
- A "/" may follow the word with the following items:
|
||
= Case must match exactly.
|
||
? Rare word.
|
||
! Bad (wrong) word.
|
||
digit A region in which the word is valid. If no regions are
|
||
specified the word is valid in all regions.
|
||
|
||
Example:
|
||
|
||
# This is an example word list comment
|
||
/encoding=latin1 encoding of the file
|
||
/regions=uscagb regions "us", "ca" and "gb"
|
||
example word for all regions
|
||
blah/12 word for regions "us" and "ca"
|
||
vim/! bad word
|
||
Campbell/?3 rare word in region 3 "gb"
|
||
's mornings/= keep-case word
|
||
|
||
Note that when "/=" is used the same word with all upper-case letters is not
|
||
accepted. This is different from a word with mixed case that is automatically
|
||
marked as keep-case, those words may appear in all upper-case letters.
|
||
|
||
|
||
FORMAT WITH .AFF AND .DIC FILES *aff-dic-format*
|
||
|
||
There are two files: the basic word list and an affix file. The affix file
|
||
specifies settings for the language and can contain affixes. The affixes are
|
||
used to modify the basic words to get the full word list. This significantly
|
||
reduces the number of words, especially for a language like Polish. This is
|
||
called affix compression.
|
||
|
||
The basic word list and the affix file are combined with the ":mkspell"
|
||
command and results in a binary spell file. All the preprocessing has been
|
||
done, thus this file loads fast. The binary spell file format is described in
|
||
the source code (src/spell.c). But only developers need to know about it.
|
||
|
||
The preprocessing also allows us to take the Myspell language files and modify
|
||
them before the Vim word list is made. The tools for this can be found in the
|
||
"src/spell" directory.
|
||
|
||
The format for the affix and word list files is based on what Myspell uses
|
||
(the spell checker of Mozilla and OpenOffice.org). A description can be found
|
||
here:
|
||
http://lingucomponent.openoffice.org/affix.readme ~
|
||
Note that affixes are case sensitive, this isn't obvious from the description.
|
||
|
||
Vim supports quite a few extras. They are described below |spell-affix-vim|.
|
||
Attempts have been made to keep this compatible with other spell checkers, so
|
||
that the same files can often be used. One other project that offers more
|
||
than Myspell is Hunspell ( http://hunspell.sf.net ).
|
||
|
||
|
||
WORD LIST FORMAT *spell-dic-format*
|
||
|
||
A short example, with line numbers:
|
||
|
||
1 1234 ~
|
||
2 aan ~
|
||
3 Als ~
|
||
4 Etten-Leur ~
|
||
5 et al. ~
|
||
6 's-Gravenhage ~
|
||
7 's-Gravenhaags ~
|
||
8 # word that differs between regions ~
|
||
9 kado/1 ~
|
||
10 cadeau/2 ~
|
||
11 TCP,IP ~
|
||
12 /the S affix may add a 's' ~
|
||
13 bedel/S ~
|
||
|
||
The first line contains the number of words. Vim ignores it, but you do get
|
||
an error message if it's not there. *E760*
|
||
|
||
What follows is one word per line. White space at the end of the line is
|
||
ignored, all other white space matters. The encoding is specified in the
|
||
affix file |spell-SET|.
|
||
|
||
Comment lines start with '#' or '/'. See the example lines 8 and 12. Note
|
||
that putting a comment after a word is NOT allowed:
|
||
|
||
someword # comment that causes an error! ~
|
||
|
||
After the word there is an optional slash and flags. Most of these flags are
|
||
letters that indicate the affixes that can be used with this word. These are
|
||
specified with SFX and PFX lines in the .aff file, see |spell-SFX| and
|
||
|spell-PFX|. Vim allows using other flag types with the FLAG item in the
|
||
affix file |spell-FLAG|.
|
||
|
||
When the word only has lower-case letters it will also match with the word
|
||
starting with an upper-case letter.
|
||
|
||
When the word includes an upper-case letter, this means the upper-case letter
|
||
is required at this position. The same word with a lower-case letter at this
|
||
position will not match. When some of the other letters are upper-case it will
|
||
not match either.
|
||
|
||
The word with all upper-case characters will always be OK,
|
||
|
||
word list matches does not match ~
|
||
als als Als ALS ALs AlS aLs aLS
|
||
Als Als ALS als ALs AlS aLs aLS
|
||
ALS ALS als Als ALs AlS aLs aLS
|
||
AlS AlS ALS als Als ALs aLs aLS
|
||
|
||
The KEEPCASE affix ID can be used to specifically match a word with identical
|
||
case only, see below |spell-KEEPCASE|.
|
||
|
||
Note: in line 5 to 7 non-word characters are used. You can include any
|
||
character in a word. When checking the text a word still only matches when it
|
||
appears with a non-word character before and after it. For Myspell a word
|
||
starting with a non-word character probably won't work.
|
||
|
||
In line 12 the word "TCP/IP" is defined. Since the slash has a special
|
||
meaning the comma is used instead. This is defined with the SLASH item in the
|
||
affix file, see |spell-SLASH|. Note that without this SLASH item the word
|
||
will be "TCP,IP".
|
||
|
||
|
||
AFFIX FILE FORMAT *spell-aff-format* *spell-affix-vim*
|
||
|
||
*spell-affix-comment*
|
||
Comment lines in the .aff file start with a '#':
|
||
|
||
# comment line ~
|
||
|
||
Items with a fixed number of arguments can be followed by a comment. But only
|
||
if none of the arguments can contain white space. The comment must start with
|
||
a "#" character. Example:
|
||
|
||
KEEPCASE = # fix case for words with this flag ~
|
||
|
||
|
||
ENCODING *spell-SET*
|
||
|
||
The affix file can be in any encoding that is supported by "iconv". However,
|
||
in some cases the current locale should also be set properly at the time
|
||
|:mkspell| is invoked. Adding FOL/LOW/UPP lines removes this requirement
|
||
|spell-FOL|.
|
||
|
||
The encoding should be specified before anything where the encoding matters.
|
||
The encoding applies both to the affix file and the dictionary file. It is
|
||
done with a SET line:
|
||
|
||
SET utf-8 ~
|
||
|
||
The encoding can be different from the value of the 'encoding' option at the
|
||
time ":mkspell" is used. Vim will then convert everything to 'encoding' and
|
||
generate a spell file for 'encoding'. If some of the used characters to not
|
||
fit in 'encoding' you will get an error message.
|
||
*spell-affix-mbyte*
|
||
When using a multi-byte encoding it's possible to use more different affix
|
||
flags. But Myspell doesn't support that, thus you may not want to use it
|
||
anyway. For compatibility use an 8-bit encoding.
|
||
|
||
|
||
INFORMATION
|
||
|
||
These entries in the affix file can be used to add information to the spell
|
||
file. There are no restrictions on the format, but they should be in the
|
||
right encoding.
|
||
|
||
*spell-NAME* *spell-VERSION* *spell-HOME*
|
||
*spell-AUTHOR* *spell-EMAIL* *spell-COPYRIGHT*
|
||
NAME Name of the language
|
||
VERSION 1.0.1 with fixes
|
||
HOME http://www.myhome.eu
|
||
AUTHOR John Doe
|
||
EMAIL john AT Doe DOT net
|
||
COPYRIGHT LGPL
|
||
|
||
These fields are put in the .spl file as-is. The |:spellinfo| command can be
|
||
used to view the info.
|
||
|
||
*:spellinfo* *:spelli*
|
||
:spelli[nfo] Display the information for the spell file(s) used for
|
||
the current buffer.
|
||
|
||
|
||
CHARACTER TABLES
|
||
*spell-affix-chars*
|
||
When using an 8-bit encoding the affix file should define what characters are
|
||
word characters. This is because the system where ":mkspell" is used may not
|
||
support a locale with this encoding and isalpha() won't work. For example
|
||
when using "cp1250" on Unix.
|
||
*E761* *E762* *spell-FOL*
|
||
*spell-LOW* *spell-UPP*
|
||
Three lines in the affix file are needed. Simplistic example:
|
||
|
||
FOL <20><><EFBFBD> ~
|
||
LOW <20><><EFBFBD> ~
|
||
UPP <20><><EFBFBD> ~
|
||
|
||
All three lines must have exactly the same number of characters.
|
||
|
||
The "FOL" line specifies the case-folded characters. These are used to
|
||
compare words while ignoring case. For most encodings this is identical to
|
||
the lower case line.
|
||
|
||
The "LOW" line specifies the characters in lower-case. Mostly it's equal to
|
||
the "FOL" line.
|
||
|
||
The "UPP" line specifies the characters with upper-case. That is, a character
|
||
is upper-case where it's different from the character at the same position in
|
||
"FOL".
|
||
|
||
An exception is made for the German sharp s <20>. The upper-case version is
|
||
"SS". In the FOL/LOW/UPP lines it should be included, so that it's recognized
|
||
as a word character, but use the <20> character in all three.
|
||
|
||
ASCII characters should be omitted, Vim always handles these in the same way.
|
||
When the encoding is UTF-8 no word characters need to be specified.
|
||
|
||
*E763*
|
||
Vim allows you to use spell checking for several languages in the same file.
|
||
You can list them in the 'spelllang' option. As a consequence all spell files
|
||
for the same encoding must use the same word characters, otherwise they can't
|
||
be combined without errors.
|
||
|
||
If you get an E763 warning that the word tables differ you need to update your
|
||
".spl" spell files. If you downloaded the files, get the latest version of
|
||
all spell files you use. If you are only using one, e.g., German, then also
|
||
download the recent English spell files. Otherwise generate the .spl file
|
||
again with |:mkspell|. If you still get errors check the FOL, LOW and UPP
|
||
lines in the used .aff files.
|
||
|
||
The XX.ascii.spl spell file generated with the "-ascii" argument will not
|
||
contain the table with characters, so that it can be combine with spell files
|
||
for any encoding. The .add.spl files also do not contain the table.
|
||
|
||
|
||
MID-WORD CHARACTERS
|
||
*spell-midword*
|
||
Some characters are only to be considered word characters if they are used in
|
||
between two ordinary word characters. An example is the single quote: It is
|
||
often used to put text in quotes, thus it can't be recognized as a word
|
||
character, but when it appears in between word characters it must be part of
|
||
the word. This is needed to detect a spelling error such as they'are. That
|
||
should be they're, but since "they" and "are" are words themselves that would
|
||
go unnoticed.
|
||
|
||
These characters are defined with MIDWORD in the .aff file. Example:
|
||
|
||
MIDWORD '- ~
|
||
|
||
|
||
FLAG TYPES *spell-FLAG*
|
||
|
||
Flags are used to specify the affixes that can be used with a word and for
|
||
other properties of the word. Normally single-character flags are used. This
|
||
limits the number of possible flags, especially for 8-bit encodings. The FLAG
|
||
item can be used if more affixes are to be used. Possible values:
|
||
|
||
FLAG long use two-character flags
|
||
FLAG num use numbers, from 1 up to 65000
|
||
FLAG caplong use one-character flags without A-Z and two-character
|
||
flags that start with A-Z
|
||
|
||
With "FLAG num" the numbers in a list of affixes need to be separated with a
|
||
comma: "234,2143,1435". This method is inefficient, but useful if the file is
|
||
generated with a program.
|
||
|
||
When using "caplong" the two-character flags all start with a capital: "Aa",
|
||
"B1", "BB", etc. This is useful to use one-character flags for the most
|
||
common items and two-character flags for uncommon items.
|
||
|
||
Note: When using utf-8 only characters up to 65000 may be used for flags.
|
||
|
||
Note: even when using "num" or "long" the number of flags available to
|
||
compounding and prefixes is limited to about 250.
|
||
|
||
|
||
AFFIXES
|
||
*spell-PFX* *spell-SFX*
|
||
The usual PFX (prefix) and SFX (suffix) lines are supported (see the Myspell
|
||
documentation or the Aspell manual:
|
||
http://aspell.net/man-html/Affix-Compression.html).
|
||
|
||
Summary:
|
||
SFX L Y 2 ~
|
||
SFX L 0 re [^x] ~
|
||
SFX L 0 ro x ~
|
||
|
||
The first line is a header and has four fields:
|
||
SFX {flag} {combine} {count}
|
||
|
||
{flag} The name used for the suffix. Mostly it's a single letter,
|
||
but other characters can be used, see |spell-FLAG|.
|
||
|
||
{combine} Can be 'Y' or 'N'. When 'Y' then the word plus suffix can
|
||
also have a prefix. When 'N' then a prefix is not allowed.
|
||
|
||
{count} The number of lines following. If this is wrong you will get
|
||
an error message.
|
||
|
||
For PFX the fields are exactly the same.
|
||
|
||
The basic format for the following lines is:
|
||
SFX {flag} {strip} {add} {condition} {extra}
|
||
|
||
{flag} Must be the same as the {flag} used in the first line.
|
||
|
||
{strip} Characters removed from the basic word. There is no check if
|
||
the characters are actually there, only the length is used (in
|
||
bytes). This better match the {condition}, otherwise strange
|
||
things may happen. If the {strip} length is equal to or
|
||
longer than the basic word the suffix won't be used.
|
||
When {strip} is 0 (zero) then nothing is stripped.
|
||
|
||
{add} Characters added to the basic word, after removing {strip}.
|
||
Optionally there is a '/' followed by flags. The flags apply
|
||
to the word plus affix. See |spell-affix-flags|
|
||
|
||
{condition} A simplistic pattern. Only when this matches with a basic
|
||
word will the suffix be used for that word. This is normally
|
||
for using one suffix letter with different {add} and {strip}
|
||
fields for words with different endings.
|
||
When {condition} is a . (dot) there is no condition.
|
||
The pattern may contain:
|
||
- Literal characters.
|
||
- A set of characters in []. [abc] matches a, b and c.
|
||
A dash is allowed for a range [a-c], but this is
|
||
Vim-specific.
|
||
- A set of characters that starts with a ^, meaning the
|
||
complement of the specified characters. [^abc] matches any
|
||
character but a, b and c.
|
||
|
||
{extra} Optional extra text:
|
||
# comment Comment is ignored
|
||
- Hunspell uses this, ignored
|
||
|
||
For PFX the fields are the same, but the {strip}, {add} and {condition} apply
|
||
to the start of the word.
|
||
|
||
Note: Myspell ignores any extra text after the relevant info. Vim requires
|
||
this text to start with a "#" so that mistakes don't go unnoticed. Example:
|
||
|
||
SFX F 0 in [^i]n # Spion > Spionin ~
|
||
SFX F 0 nen in # Bauerin > Bauerinnen ~
|
||
|
||
However, to avoid lots of errors in affix files written for Myspell, you can
|
||
add the IGNOREEXTRA flag.
|
||
|
||
Apparently Myspell allows an affix name to appear more than once. Since this
|
||
might also be a mistake, Vim checks for an extra "S". The affix files for
|
||
Myspell that use this feature apparently have this flag. Example:
|
||
|
||
SFX a Y 1 S ~
|
||
SFX a 0 an . ~
|
||
|
||
SFX a Y 2 S ~
|
||
SFX a 0 en . ~
|
||
SFX a 0 on . ~
|
||
|
||
|
||
AFFIX FLAGS *spell-affix-flags*
|
||
|
||
This is a feature that comes from Hunspell: The affix may specify flags. This
|
||
works similar to flags specified on a basic word. The flags apply to the
|
||
basic word plus the affix (but there are restrictions). Example:
|
||
|
||
SFX S Y 1 ~
|
||
SFX S 0 s . ~
|
||
|
||
SFX A Y 1 ~
|
||
SFX A 0 able/S . ~
|
||
|
||
When the dictionary file contains "drink/AS" then these words are possible:
|
||
|
||
drink
|
||
drinks uses S suffix
|
||
drinkable uses A suffix
|
||
drinkables uses A suffix and then S suffix
|
||
|
||
Generally the flags of the suffix are added to the flags of the basic word,
|
||
both are used for the word plus suffix. But the flags of the basic word are
|
||
only used once for affixes, except that both one prefix and one suffix can be
|
||
used when both support combining.
|
||
|
||
Specifically, the affix flags can be used for:
|
||
- Suffixes on suffixes, as in the example above. This works once, thus you
|
||
can have two suffixes on a word (plus one prefix).
|
||
- Making the word with the affix rare, by using the |spell-RARE| flag.
|
||
- Exclude the word with the affix from compounding, by using the
|
||
|spell-COMPOUNDFORBIDFLAG| flag.
|
||
- Allow the word with the affix to be part of a compound word on the side of
|
||
the affix with the |spell-COMPOUNDPERMITFLAG|.
|
||
- Use the NEEDCOMPOUND flag: word plus affix can only be used as part of a
|
||
compound word. |spell-NEEDCOMPOUND|
|
||
- Compound flags: word plus affix can be part of a compound word at the end,
|
||
middle, start, etc. The flags are combined with the flags of the basic
|
||
word. |spell-compound|
|
||
- NEEDAFFIX: another affix is needed to make a valid word.
|
||
- CIRCUMFIX, as explained just below.
|
||
|
||
|
||
IGNOREEXTRA *spell-IGNOREEXTRA*
|
||
|
||
Normally Vim gives an error for an extra field that does not start with '#'.
|
||
This avoids errors going unnoticed. However, some files created for Myspell
|
||
or Hunspell may contain many entries with an extra field. Use the IGNOREEXTRA
|
||
flag to avoid lots of errors.
|
||
|
||
|
||
CIRCUMFIX *spell-CIRCUMFIX*
|
||
|
||
The CIRCUMFIX flag means a prefix and suffix must be added at the same time.
|
||
If a prefix has the CIRCUMFIX flag than only suffixes with the CIRCUMFIX flag
|
||
can be added, and the other way around.
|
||
An alternative is to only specify the suffix, and give the that suffix two
|
||
flags: The required prefix and the NEEDAFFIX flag. |spell-NEEDAFFIX|
|
||
|
||
|
||
PFXPOSTPONE *spell-PFXPOSTPONE*
|
||
|
||
When an affix file has very many prefixes that apply to many words it's not
|
||
possible to build the whole word list in memory. This applies to Hebrew (a
|
||
list with all words is over a Gbyte). In that case applying prefixes must be
|
||
postponed. This makes spell checking slower. It is indicated by this keyword
|
||
in the .aff file:
|
||
|
||
PFXPOSTPONE ~
|
||
|
||
Only prefixes without a chop string and without flags can be postponed.
|
||
Prefixes with a chop string or with flags will still be included in the word
|
||
list. An exception if the chop string is one character and equal to the last
|
||
character of the added string, but in lower case. Thus when the chop string
|
||
is used to allow the following word to start with an upper case letter.
|
||
|
||
|
||
WORDS WITH A SLASH *spell-SLASH*
|
||
|
||
The slash is used in the .dic file to separate the basic word from the affix
|
||
letters and other flags. Unfortunately, this means you cannot use a slash in
|
||
a word. Thus "TCP/IP" is not a word but "TCP" with the flags "IP". To include
|
||
a slash in the word put a backslash before it: "TCP\/IP". In the rare case
|
||
you want to use a backslash inside a word you need to use two backslashes.
|
||
Any other use of the backslash is reserved for future expansion.
|
||
|
||
|
||
KEEP-CASE WORDS *spell-KEEPCASE*
|
||
|
||
In the affix file a KEEPCASE line can be used to define the affix name used
|
||
for keep-case words. Example:
|
||
|
||
KEEPCASE = ~
|
||
|
||
This flag is not supported by Myspell. It has the meaning that case matters.
|
||
This can be used if the word does not have the first letter in upper case at
|
||
the start of a sentence. Example:
|
||
|
||
word list matches does not match ~
|
||
's morgens/= 's morgens 'S morgens 's Morgens 'S MORGENS
|
||
's Morgens 's Morgens 'S MORGENS 'S morgens 's morgens
|
||
|
||
The flag can also be used to avoid that the word matches when it is in all
|
||
upper-case letters.
|
||
|
||
|
||
RARE WORDS *spell-RARE*
|
||
|
||
In the affix file a RARE line can be used to define the affix name used for
|
||
rare words. Example:
|
||
|
||
RARE ? ~
|
||
|
||
Rare words are highlighted differently from bad words. This is to be used for
|
||
words that are correct for the language, but are hardly ever used and could be
|
||
a typing mistake anyway.
|
||
|
||
This flag can also be used on an affix, so that a basic word is not rare but
|
||
the basic word plus affix is rare |spell-affix-flags|. However, if the word
|
||
also appears as a good word in another way (e.g., in another region) it won't
|
||
be marked as rare.
|
||
|
||
|
||
BAD WORDS *spell-BAD*
|
||
|
||
In the affix file a BAD line can be used to define the affix name used for
|
||
bad words. Example:
|
||
|
||
BAD ! ~
|
||
|
||
This can be used to exclude words that would otherwise be good. For example
|
||
"the the" in the .dic file:
|
||
|
||
the the/! ~
|
||
|
||
Once a word has been marked as bad it won't be undone by encountering the same
|
||
word as good.
|
||
|
||
The flag also applies to the word with affixes, thus this can be used to mark
|
||
a whole bunch of related words as bad.
|
||
|
||
*spell-FORBIDDENWORD*
|
||
FORBIDDENWORD can be used just like BAD. For compatibility with Hunspell.
|
||
|
||
*spell-NEEDAFFIX*
|
||
The NEEDAFFIX flag is used to require that a word is used with an affix. The
|
||
word itself is not a good word (unless there is an empty affix). Example:
|
||
|
||
NEEDAFFIX + ~
|
||
|
||
|
||
COMPOUND WORDS *spell-compound*
|
||
|
||
A compound word is a longer word made by concatenating words that appear in
|
||
the .dic file. To specify which words may be concatenated a character is
|
||
used. This character is put in the list of affixes after the word. We will
|
||
call this character a flag here. Obviously these flags must be different from
|
||
any affix IDs used.
|
||
|
||
*spell-COMPOUNDFLAG*
|
||
The Myspell compatible method uses one flag, specified with COMPOUNDFLAG. All
|
||
words with this flag combine in any order. This means there is no control
|
||
over which word comes first. Example:
|
||
COMPOUNDFLAG c ~
|
||
|
||
*spell-COMPOUNDRULE*
|
||
A more advanced method to specify how compound words can be formed uses
|
||
multiple items with multiple flags. This is not compatible with Myspell 3.0.
|
||
Let's start with an example:
|
||
COMPOUNDRULE c+ ~
|
||
COMPOUNDRULE se ~
|
||
|
||
The first line defines that words with the "c" flag can be concatenated in any
|
||
order. The second line defines compound words that are made of one word with
|
||
the "s" flag and one word with the "e" flag. With this dictionary:
|
||
bork/c ~
|
||
onion/s ~
|
||
soup/e ~
|
||
|
||
You can make these words:
|
||
bork
|
||
borkbork
|
||
borkborkbork
|
||
(etc.)
|
||
onion
|
||
soup
|
||
onionsoup
|
||
|
||
The COMPOUNDRULE item may appear multiple times. The argument is made out of
|
||
one or more groups, where each group can be:
|
||
one flag e.g., c
|
||
alternate flags inside [] e.g., [abc]
|
||
Optionally this may be followed by:
|
||
* the group appears zero or more times, e.g., sm*e
|
||
+ the group appears one or more times, e.g., c+
|
||
? the group appears zero times or once, e.g., x?
|
||
|
||
This is similar to the regexp pattern syntax (but not the same!). A few
|
||
examples with the sequence of word flags they require:
|
||
COMPOUNDRULE x+ x xx xxx etc.
|
||
COMPOUNDRULE yz yz
|
||
COMPOUNDRULE x+z xz xxz xxxz etc.
|
||
COMPOUNDRULE yx+ yx yxx yxxx etc.
|
||
COMPOUNDRULE xy?z xz xyz
|
||
|
||
COMPOUNDRULE [abc]z az bz cz
|
||
COMPOUNDRULE [abc]+z az aaz abaz bz baz bcbz cz caz cbaz etc.
|
||
COMPOUNDRULE a[xyz]+ ax axx axyz ay ayx ayzz az azy azxy etc.
|
||
COMPOUNDRULE sm*e se sme smme smmme etc.
|
||
COMPOUNDRULE s[xyz]*e se sxe sxye sxyxe sye syze sze szye szyxe etc.
|
||
|
||
A specific example: Allow a compound to be made of two words and a dash:
|
||
In the .aff file:
|
||
COMPOUNDRULE sde ~
|
||
NEEDAFFIX x ~
|
||
COMPOUNDWORDMAX 3 ~
|
||
COMPOUNDMIN 1 ~
|
||
In the .dic file:
|
||
start/s ~
|
||
end/e ~
|
||
-/xd ~
|
||
|
||
This allows for the word "start-end", but not "startend".
|
||
|
||
An additional implied rule is that, without further flags, a word with a
|
||
prefix cannot be compounded after another word, and a word with a suffix
|
||
cannot be compounded with a following word. Thus the affix cannot appear
|
||
on the inside of a compound word. This can be changed with the
|
||
|spell-COMPOUNDPERMITFLAG|.
|
||
|
||
*spell-NEEDCOMPOUND*
|
||
The NEEDCOMPOUND flag is used to require that a word is used as part of a
|
||
compound word. The word itself is not a good word. Example:
|
||
|
||
NEEDCOMPOUND & ~
|
||
|
||
*spell-ONLYINCOMPOUND*
|
||
The ONLYINCOMPOUND does exactly the same as NEEDCOMPOUND. Supported for
|
||
compatibility with Hunspell.
|
||
|
||
*spell-COMPOUNDMIN*
|
||
The minimal character length of a word used for compounding is specified with
|
||
COMPOUNDMIN. Example:
|
||
COMPOUNDMIN 5 ~
|
||
|
||
When omitted there is no minimal length. Obviously you could just leave out
|
||
the compound flag from short words instead, this feature is present for
|
||
compatibility with Myspell.
|
||
|
||
*spell-COMPOUNDWORDMAX*
|
||
The maximum number of words that can be concatenated into a compound word is
|
||
specified with COMPOUNDWORDMAX. Example:
|
||
COMPOUNDWORDMAX 3 ~
|
||
|
||
When omitted there is no maximum. It applies to all compound words.
|
||
|
||
To set a limit for words with specific flags make sure the items in
|
||
COMPOUNDRULE where they appear don't allow too many words.
|
||
|
||
*spell-COMPOUNDSYLMAX*
|
||
The maximum number of syllables that a compound word may contain is specified
|
||
with COMPOUNDSYLMAX. Example:
|
||
COMPOUNDSYLMAX 6 ~
|
||
|
||
This has no effect if there is no SYLLABLE item. Without COMPOUNDSYLMAX there
|
||
is no limit on the number of syllables.
|
||
|
||
If both COMPOUNDWORDMAX and COMPOUNDSYLMAX are defined, a compound word is
|
||
accepted if it fits one of the criteria, thus is either made from up to
|
||
COMPOUNDWORDMAX words or contains up to COMPOUNDSYLMAX syllables.
|
||
|
||
*spell-COMPOUNDFORBIDFLAG*
|
||
The COMPOUNDFORBIDFLAG specifies a flag that can be used on an affix. It
|
||
means that the word plus affix cannot be used in a compound word. Example:
|
||
affix file:
|
||
COMPOUNDFLAG c ~
|
||
COMPOUNDFORBIDFLAG x ~
|
||
SFX a Y 2 ~
|
||
SFX a 0 s . ~
|
||
SFX a 0 ize/x . ~
|
||
dictionary:
|
||
word/c ~
|
||
util/ac ~
|
||
|
||
This allows for "wordutil" and "wordutils" but not "wordutilize".
|
||
Note: this doesn't work for postponed prefixes yet.
|
||
|
||
*spell-COMPOUNDPERMITFLAG*
|
||
The COMPOUNDPERMITFLAG specifies a flag that can be used on an affix. It
|
||
means that the word plus affix can also be used in a compound word in a way
|
||
where the affix ends up halfway through the word. Without this flag that is
|
||
not allowed.
|
||
Note: this doesn't work for postponed prefixes yet.
|
||
|
||
*spell-COMPOUNDROOT*
|
||
The COMPOUNDROOT flag is used for words in the dictionary that are already a
|
||
compound. This means it counts for two words when checking the compounding
|
||
rules. Can also be used for an affix to count the affix as a compounding
|
||
word.
|
||
|
||
*spell-CHECKCOMPOUNDPATTERN*
|
||
CHECKCOMPOUNDPATTERN is used to define patterns that, when matching at the
|
||
position where two words are compounded together forbids the compound.
|
||
For example:
|
||
CHECKCOMPOUNDPATTERN o e ~
|
||
|
||
This forbids compounding if the first word ends in "o" and the second word
|
||
starts with "e".
|
||
|
||
The arguments must be plain text, no patterns are actually supported, despite
|
||
the item name. Case is always ignored.
|
||
|
||
The Hunspell feature to use three arguments and flags is not supported.
|
||
|
||
*spell-NOCOMPOUNDSUGS*
|
||
This item indicates that using compounding to make suggestions is not a good
|
||
idea. Use this when compounding is used with very short or one-character
|
||
words. E.g. to make numbers out of digits. Without this flag creating
|
||
suggestions would spend most time trying all kind of weird compound words.
|
||
|
||
NOCOMPOUNDSUGS ~
|
||
|
||
*spell-SYLLABLE*
|
||
The SYLLABLE item defines characters or character sequences that are used to
|
||
count the number of syllables in a word. Example:
|
||
SYLLABLE a<>e<EFBFBD>i<EFBFBD>o<EFBFBD><6F><EFBFBD>u<EFBFBD><75><EFBFBD>y/aa/au/ea/ee/ei/ie/oa/oe/oo/ou/uu/ui ~
|
||
|
||
Before the first slash is the set of characters that are counted for one
|
||
syllable, also when repeated and mixed, until the next character that is not
|
||
in this set. After the slash come sequences of characters that are counted
|
||
for one syllable. These are preferred over using characters from the set.
|
||
With the example "ideeen" has three syllables, counted by "i", "ee" and "e".
|
||
|
||
Only case-folded letters need to be included.
|
||
|
||
Another way to restrict compounding was mentioned above: Adding the
|
||
|spell-COMPOUNDFORBIDFLAG| flag to an affix causes all words that are made
|
||
with that affix to not be used for compounding.
|
||
|
||
|
||
UNLIMITED COMPOUNDING *spell-NOBREAK*
|
||
|
||
For some languages, such as Thai, there is no space in between words. This
|
||
looks like all words are compounded. To specify this use the NOBREAK item in
|
||
the affix file, without arguments:
|
||
NOBREAK ~
|
||
|
||
Vim will try to figure out where one word ends and a next starts. When there
|
||
are spelling mistakes this may not be quite right.
|
||
|
||
|
||
*spell-COMMON*
|
||
Common words can be specified with the COMMON item. This will give better
|
||
suggestions when editing a short file. Example:
|
||
|
||
COMMON the of to and a in is it you that he was for on are ~
|
||
|
||
The words must be separated by white space, up to 25 per line.
|
||
When multiple regions are specified in a ":mkspell" command the common words
|
||
for all regions are combined and used for all regions.
|
||
|
||
*spell-NOSPLITSUGS*
|
||
This item indicates that splitting a word to make suggestions is not a good
|
||
idea. Split-word suggestions will appear only when there are few similar
|
||
words.
|
||
|
||
NOSPLITSUGS ~
|
||
|
||
*spell-NOSUGGEST*
|
||
The flag specified with NOSUGGEST can be used for words that will not be
|
||
suggested. Can be used for obscene words.
|
||
|
||
NOSUGGEST % ~
|
||
|
||
|
||
REPLACEMENTS *spell-REP*
|
||
|
||
In the affix file REP items can be used to define common mistakes. This is
|
||
used to make spelling suggestions. The items define the "from" text and the
|
||
"to" replacement. Example:
|
||
|
||
REP 4 ~
|
||
REP f ph ~
|
||
REP ph f ~
|
||
REP k ch ~
|
||
REP ch k ~
|
||
|
||
The first line specifies the number of REP lines following. Vim ignores the
|
||
number, but it must be there (for compatibility with Myspell).
|
||
|
||
Don't include simple one-character replacements or swaps. Vim will try these
|
||
anyway. You can include whole words if you want to, but you might want to use
|
||
the "file:" item in 'spellsuggest' instead.
|
||
|
||
You can include a space by using an underscore:
|
||
|
||
REP the_the the ~
|
||
|
||
|
||
SIMILAR CHARACTERS *spell-MAP* *E783*
|
||
|
||
In the affix file MAP items can be used to define letters that are very much
|
||
alike. This is mostly used for a letter with different accents. This is used
|
||
to prefer suggestions with these letters substituted. Example:
|
||
|
||
MAP 2 ~
|
||
MAP e<><65><EFBFBD><EFBFBD> ~
|
||
MAP u<><75><EFBFBD><EFBFBD> ~
|
||
|
||
The first line specifies the number of MAP lines following. Vim ignores the
|
||
number, but the line must be there.
|
||
|
||
Each letter must appear in only one of the MAP items. It's a bit more
|
||
efficient if the first letter is ASCII or at least one without accents.
|
||
|
||
|
||
.SUG FILE *spell-NOSUGFILE*
|
||
|
||
When soundfolding is specified in the affix file then ":mkspell" will normally
|
||
produce a .sug file next to the .spl file. This file is used to find
|
||
suggestions by their sound-a-like form quickly. At the cost of a lot of
|
||
memory (the amount depends on the number of words, |:mkspell| will display an
|
||
estimate when it's done).
|
||
|
||
To avoid producing a .sug file use this item in the affix file:
|
||
|
||
NOSUGFILE ~
|
||
|
||
Users can simply omit the .sug file if they don't want to use it.
|
||
|
||
|
||
SOUND-A-LIKE *spell-SAL*
|
||
|
||
In the affix file SAL items can be used to define the sounds-a-like mechanism
|
||
to be used. The main items define the "from" text and the "to" replacement.
|
||
Simplistic example:
|
||
|
||
SAL CIA X ~
|
||
SAL CH X ~
|
||
SAL C K ~
|
||
SAL K K ~
|
||
|
||
There are a few rules and this can become quite complicated. An explanation
|
||
how it works can be found in the Aspell manual:
|
||
http://aspell.net/man-html/Phonetic-Code.html.
|
||
|
||
There are a few special items:
|
||
|
||
SAL followup true ~
|
||
SAL collapse_result true ~
|
||
SAL remove_accents true ~
|
||
|
||
"1" has the same meaning as "true". Any other value means "false".
|
||
|
||
|
||
SIMPLE SOUNDFOLDING *spell-SOFOFROM* *spell-SOFOTO*
|
||
|
||
The SAL mechanism is complex and slow. A simpler mechanism is mapping all
|
||
characters to another character, mapping similar sounding characters to the
|
||
same character. At the same time this does case folding. You can not have
|
||
both SAL items and simple soundfolding.
|
||
|
||
There are two items required: one to specify the characters that are mapped
|
||
and one that specifies the characters they are mapped to. They must have
|
||
exactly the same number of characters. Example:
|
||
|
||
SOFOFROM abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ ~
|
||
SOFOTO ebctefghejklnnepkrstevvkesebctefghejklnnepkrstevvkes ~
|
||
|
||
In the example all vowels are mapped to the same character 'e'. Another
|
||
method would be to leave out all vowels. Some characters that sound nearly
|
||
the same and are often mixed up, such as 'm' and 'n', are mapped to the same
|
||
character. Don't do this too much, all words will start looking alike.
|
||
|
||
Characters that do not appear in SOFOFROM will be left out, except that all
|
||
white space is replaced by one space. Sequences of the same character in
|
||
SOFOFROM are replaced by one.
|
||
|
||
You can use the |soundfold()| function to try out the results. Or set the
|
||
'verbose' option to see the score in the output of the |z=| command.
|
||
|
||
|
||
UNSUPPORTED ITEMS *spell-affix-not-supported*
|
||
|
||
These items appear in the affix file of other spell checkers. In Vim they are
|
||
ignored, not supported or defined in another way.
|
||
|
||
ACCENT (Hunspell) *spell-ACCENT*
|
||
Use MAP instead. |spell-MAP|
|
||
|
||
BREAK (Hunspell) *spell-BREAK*
|
||
Define break points. Unclear how it works exactly.
|
||
Not supported.
|
||
|
||
CHECKCOMPOUNDCASE (Hunspell) *spell-CHECKCOMPOUNDCASE*
|
||
Disallow uppercase letters at compound word boundaries.
|
||
Not supported.
|
||
|
||
CHECKCOMPOUNDDUP (Hunspell) *spell-CHECKCOMPOUNDDUP*
|
||
Disallow using the same word twice in a compound. Not
|
||
supported.
|
||
|
||
CHECKCOMPOUNDREP (Hunspell) *spell-CHECKCOMPOUNDREP*
|
||
Something about using REP items and compound words. Not
|
||
supported.
|
||
|
||
CHECKCOMPOUNDTRIPLE (Hunspell) *spell-CHECKCOMPOUNDTRIPLE*
|
||
Forbid three identical characters when compounding. Not
|
||
supported.
|
||
|
||
COMPLEXPREFIXES (Hunspell) *spell-COMPLEXPREFIXES*
|
||
Enables using two prefixes. Not supported.
|
||
|
||
COMPOUND (Hunspell) *spell-COMPOUND*
|
||
This is one line with the count of COMPOUND items, followed by
|
||
that many COMPOUND lines with a pattern.
|
||
Remove the first line with the count and rename the other
|
||
items to COMPOUNDRULE |spell-COMPOUNDRULE|
|
||
|
||
COMPOUNDFIRST (Hunspell) *spell-COMPOUNDFIRST*
|
||
Use COMPOUNDRULE instead. |spell-COMPOUNDRULE|
|
||
|
||
COMPOUNDBEGIN (Hunspell) *spell-COMPOUNDBEGIN*
|
||
Use COMPOUNDRULE instead. |spell-COMPOUNDRULE|
|
||
|
||
COMPOUNDEND (Hunspell) *spell-COMPOUNDEND*
|
||
Use COMPOUNDRULE instead. |spell-COMPOUNDRULE|
|
||
|
||
COMPOUNDMIDDLE (Hunspell) *spell-COMPOUNDMIDDLE*
|
||
Use COMPOUNDRULE instead. |spell-COMPOUNDRULE|
|
||
|
||
COMPOUNDRULES (Hunspell) *spell-COMPOUNDRULES*
|
||
Number of COMPOUNDRULE lines following. Ignored, but the
|
||
argument must be a number.
|
||
|
||
COMPOUNDSYLLABLE (Hunspell) *spell-COMPOUNDSYLLABLE*
|
||
Use SYLLABLE and COMPOUNDSYLMAX instead. |spell-SYLLABLE|
|
||
|spell-COMPOUNDSYLMAX|
|
||
|
||
KEY (Hunspell) *spell-KEY*
|
||
Define characters that are close together on the keyboard.
|
||
Used to give better suggestions. Not supported.
|
||
|
||
LANG (Hunspell) *spell-LANG*
|
||
This specifies language-specific behavior. This actually
|
||
moves part of the language knowledge into the program,
|
||
therefore Vim does not support it. Each language property
|
||
must be specified separately.
|
||
|
||
LEMMA_PRESENT (Hunspell) *spell-LEMMA_PRESENT*
|
||
Only needed for morphological analysis.
|
||
|
||
MAXNGRAMSUGS (Hunspell) *spell-MAXNGRAMSUGS*
|
||
Set number of n-gram suggestions. Not supported.
|
||
|
||
PSEUDOROOT (Hunspell) *spell-PSEUDOROOT*
|
||
Use NEEDAFFIX instead. |spell-NEEDAFFIX|
|
||
|
||
SUGSWITHDOTS (Hunspell) *spell-SUGSWITHDOTS*
|
||
Adds dots to suggestions. Vim doesn't need this.
|
||
|
||
SYLLABLENUM (Hunspell) *spell-SYLLABLENUM*
|
||
Not supported.
|
||
|
||
TRY (Myspell, Hunspell, others) *spell-TRY*
|
||
Vim does not use the TRY item, it is ignored. For making
|
||
suggestions the actual characters in the words are used, that
|
||
is much more efficient.
|
||
|
||
WORDCHARS (Hunspell) *spell-WORDCHARS*
|
||
Used to recognize words. Vim doesn't need it, because there
|
||
is no need to separate words before checking them (using a
|
||
trie instead of a hashtable).
|
||
|
||
==============================================================================
|
||
5. Spell checker design *develop-spell*
|
||
|
||
When spell checking was going to be added to Vim a survey was done over the
|
||
available spell checking libraries and programs. Unfortunately, the result
|
||
was that none of them provided sufficient capabilities to be used as the spell
|
||
checking engine in Vim, for various reasons:
|
||
|
||
- Missing support for multi-byte encodings. At least UTF-8 must be supported,
|
||
so that more than one language can be used in the same file.
|
||
Doing on-the-fly conversion is not always possible (would require iconv
|
||
support).
|
||
- For the programs and libraries: Using them as-is would require installing
|
||
them separately from Vim. That's mostly not impossible, but a drawback.
|
||
- Performance: A few tests showed that it's possible to check spelling on the
|
||
fly (while redrawing), just like syntax highlighting. But the mechanisms
|
||
used by other code are much slower. Myspell uses a hashtable, for example.
|
||
The affix compression that most spell checkers use makes it slower too.
|
||
- For using an external program like aspell a communication mechanism would
|
||
have to be setup. That's complicated to do in a portable way (Unix-only
|
||
would be relatively simple, but that's not good enough). And performance
|
||
will become a problem (lots of process switching involved).
|
||
- Missing support for words with non-word characters, such as "Etten-Leur" and
|
||
"et al.", would require marking the pieces of them OK, lowering the
|
||
reliability.
|
||
- Missing support for regions or dialects. Makes it difficult to accept
|
||
all English words and highlight non-Canadian words differently.
|
||
- Missing support for rare words. Many words are correct but hardly ever used
|
||
and could be a misspelled often-used word.
|
||
- For making suggestions the speed is less important and requiring to install
|
||
another program or library would be acceptable. But the word lists probably
|
||
differ, the suggestions may be wrong words.
|
||
|
||
|
||
Spelling suggestions *develop-spell-suggestions*
|
||
|
||
For making suggestions there are two basic mechanisms:
|
||
1. Try changing the bad word a little bit and check for a match with a good
|
||
word. Or go through the list of good words, change them a little bit and
|
||
check for a match with the bad word. The changes are deleting a character,
|
||
inserting a character, swapping two characters, etc.
|
||
2. Perform soundfolding on both the bad word and the good words and then find
|
||
matches, possibly with a few changes like with the first mechanism.
|
||
|
||
The first is good for finding typing mistakes. After experimenting with
|
||
hashtables and looking at solutions from other spell checkers the conclusion
|
||
was that a trie (a kind of tree structure) is ideal for this. Both for
|
||
reducing memory use and being able to try sensible changes. For example, when
|
||
inserting a character only characters that lead to good words need to be
|
||
tried. Other mechanisms (with hashtables) need to try all possible letters at
|
||
every position in the word. Also, a hashtable has the requirement that word
|
||
boundaries are identified separately, while a trie does not require this.
|
||
That makes the mechanism a lot simpler.
|
||
|
||
Soundfolding is useful when someone knows how the words sounds but doesn't
|
||
know how it is spelled. For example, the word "dictionary" might be written
|
||
as "daktonerie". The number of changes that the first method would need to
|
||
try is very big, it's hard to find the good word that way. After soundfolding
|
||
the words become "tktnr" and "tkxnry", these differ by only two letters.
|
||
|
||
To find words by their soundfolded equivalent (soundalike word) we need a list
|
||
of all soundfolded words. A few experiments have been done to find out what
|
||
the best method is. Alternatives:
|
||
1. Do the sound folding on the fly when looking for suggestions. This means
|
||
walking through the trie of good words, soundfolding each word and
|
||
checking how different it is from the bad word. This is very efficient for
|
||
memory use, but takes a long time. On a fast PC it takes a couple of
|
||
seconds for English, which can be acceptable for interactive use. But for
|
||
some languages it takes more than ten seconds (e.g., German, Catalan),
|
||
which is unacceptable slow. For batch processing (automatic corrections)
|
||
it's too slow for all languages.
|
||
2. Use a trie for the soundfolded words, so that searching can be done just
|
||
like how it works without soundfolding. This requires remembering a list
|
||
of good words for each soundfolded word. This makes finding matches very
|
||
fast but requires quite a lot of memory, in the order of 1 to 10 Mbyte.
|
||
For some languages more than the original word list.
|
||
3. Like the second alternative, but reduce the amount of memory by using affix
|
||
compression and store only the soundfolded basic word. This is what Aspell
|
||
does. Disadvantage is that affixes need to be stripped from the bad word
|
||
before soundfolding it, which means that mistakes at the start and/or end
|
||
of the word will cause the mechanism to fail. Also, this becomes slow when
|
||
the bad word is quite different from the good word.
|
||
|
||
The choice made is to use the second mechanism and use a separate file. This
|
||
way a user with sufficient memory can get very good suggestions while a user
|
||
who is short of memory or just wants the spell checking and no suggestions
|
||
doesn't use so much memory.
|
||
|
||
|
||
Word frequency
|
||
|
||
For sorting suggestions it helps to know which words are common. In theory we
|
||
could store a word frequency with the word in the dictionary. However, this
|
||
requires storing a count per word. That degrades word tree compression a lot.
|
||
And maintaining the word frequency for all languages will be a heavy task.
|
||
Also, it would be nice to prefer words that are already in the text. This way
|
||
the words that appear in the specific text are preferred for suggestions.
|
||
|
||
What has been implemented is to count words that have been seen during
|
||
displaying. A hashtable is used to quickly find the word count. The count is
|
||
initialized from words listed in COMMON items in the affix file, so that it
|
||
also works when starting a new file.
|
||
|
||
This isn't ideal, because the longer Vim is running the higher the counts
|
||
become. But in practice it is a noticeable improvement over not using the word
|
||
count.
|
||
|
||
vim:tw=78:sw=4:ts=8:ft=help:norl:
|