Vim Syntax Highlighting: Implicit Conceal and Syntax Patterns

higher priority than other items. Example: > :syn match ifstart "\<if.*" nextgroup=ifline skipwhite skipempty :syn match ifline "[^ \t].*" nextgroup=ifline skipwhite skipempty contained :syn match ifline "endif" contained Note that the "[^ \t].*" match matches all non-white text. Thus it would also match "endif". Therefore the "endif" match is put last, so that it takes precedence. Note that this example doesn't work for nested "if"s. You need to add "contains" arguments to make that work (omitted for simplicity of the example). IMPLICIT CONCEAL *:syn-conceal-implicit* :sy[ntax] conceal [on|off] This defines if the following ":syntax" commands will define keywords, matches or regions with the "conceal" flag set. After ":syn conceal on", all subsequent ":syn keyword", ":syn match" or ":syn region" defined will have the "conceal" flag set implicitly. ":syn conceal off" returns to the normal state where the "conceal" flag must be given explicitly. :sy[ntax] conceal Show either "syntax conceal on" or "syntax conceal off". ============================================================================== 8. Syntax patterns *:syn-pattern* *E401* *E402* In the syntax commands, a pattern must be surrounded by two identical characters. This is like it works for the ":s" command. The most common to use is the double quote. But if the pattern contains a double quote, you can use another character that is not used in the pattern. Examples: > :syntax region Comment start="/\*" end="\*/" :syntax region String start=+"+ end=+"+ skip=+\\"+ See |pattern| for the explanation of what a pattern is. Syntax patterns are always interpreted like the 'magic' option is set, no matter what the actual value of 'magic' is. And the patterns are interpreted like the 'l' flag is not included in 'cpoptions'. This was done to make syntax files portable and independent of the 'magic' setting. Try to avoid patterns that can match an empty string, such as "[a-z]*". This slows down the highlighting a lot, because it matches everywhere. *:syn-pattern-offset* The pattern can be followed by a character offset. This can be used to change the highlighted part, and to change the text area included in the match or region (which only matters when trying to match other items). Both are relative to the matched pattern. The character offset for a skip pattern can be used to tell where to continue looking for an end pattern. The offset takes the form of "{what}={offset}" The {what} can be one of seven strings: ms Match Start offset for the start of the matched text me Match End offset for the end of the matched text hs Highlight Start offset for where the highlighting starts he Highlight End offset for where the highlighting ends rs Region Start offset for where the body of a region starts re Region End offset for where the body of a region ends lc Leading Context offset past "leading context" of pattern The {offset} can be: s start of the matched pattern s+{nr} start of the matched pattern plus {nr} chars to the right s-{nr} start of the matched pattern plus {nr} chars to the left e end of the matched pattern e+{nr} end of the matched pattern plus {nr} chars to the right e-{nr} end of the matched pattern plus {nr} chars to the left {nr} (for "lc" only): start matching {nr} chars right of the start Examples: "ms=s+1", "hs=e-2", "lc=3". Although all offsets are accepted after any pattern, they are not always meaningful. This table shows which offsets are actually used: ms me hs he rs re lc ~ match item yes yes yes yes - - yes region item start yes - yes - yes - yes region item skip - yes - - - - yes region item end - yes - yes - yes yes Offsets can be concatenated, with a ',' in between. Example: > :syn match String /"[^"]*"/hs=s+1,he=e-1 < some "string" text ^^^^^^ highlighted Notes: - There must be no white space between the pattern and

This section explains the use of `:syntax conceal [on|off]` to control whether subsequent syntax commands automatically set the "conceal" flag. It transitions to syntax patterns, describing how patterns are defined with delimiters and how Vim interprets them with 'magic' set and 'l' flag excluded from 'cpoptions'. It warns against patterns that match empty strings. It introduces character offsets (ms, me, hs, he, rs, re, lc) to adjust the highlighted portion or text area included in a match or region, relative to the matched pattern.