Add syntax highlighting for *.mld

Co-authored-by: Samuel Hym <[email protected]>

Author: n-osborne

doc/ocaml.txt

@@ -9,6 +9,13 @@ highlighted. You can turn on highlighting of operators by defining:
 
   let g:ocaml_highlight_operators = 1
 
+                                                         *g:odoc_html_support*
+
+By default HTML code inlined in OCamldoc/Odoc syntax is not highlighted to
+avoid loading the HTML syntax. You can turn on HTML highlighting by defining:
+
+  let g:odoc_html_support = 1
+
                                            *g:ocaml_compiler_compact_messages*
 
 By default the output of the OCaml compiler is filtered to keep only the

ftdetect/odoc.vim

@@ -0,0 +1 @@
+au BufNewFile,BufRead *.mld setf odoc

syntax/odoc.vim

@@ -0,0 +1,82 @@
+" Vim syntax file
+" Language:     Odoc/OCamldoc
+" Filenames:    *.mld
+" Maintainers:  Samuel Hym
+"               Nicolas Osborne
+" URL:          https://github.com/ocaml/vim-ocaml
+" Last Change:
+"               2024 Jan 26 - initial version
+
+" Quit when a syntax file was already loaded
+if !exists("odoc_syntax_loading")
+  if exists("b:current_syntax")
+    finish
+  endif
+  let odoc_syntax_loading = 1
+endif
+
+let s:keepcpo = &cpo
+set cpo&vim
+
+syn case match
+
+syn include @odocSyntaxOCaml syntax/ocaml.vim
+unlet b:current_syntax
+
+syn cluster odocInline contains=odocBold,odocItalic,odocEmphasis,odocMiscInline,odocList,odocLink,odocCode,odocCrossref,odocCodeBlock,odocVerbatim,odocTargetSpecific,odocTag
+
+syn region odocLink matchgroup=odocLinkMarker start="{" end="}" contains=odocCrossref
+syn region odocBold matchgroup=odocMarker start="{b\>" end="}" contains=@Spell,@odocInline
+syn region odocEmphasis matchgroup=odocMarker start="{e\>" end="}" contains=@Spell,@odocInline
+syn region odocItalic matchgroup=odocMarker start="{i\>" end="}" contains=@Spell,@odocInline
+syn region odocMiscInline matchgroup=odocMarker start="{[CLR^_]" end="}" contains=@Spell,@odocInline
+syn region odocVerbatim matchgroup=odocMarker start="{v\>" end="\<v}"
+
+if get(g:,'odoc_html_support',0)
+  syn include @odocHtml syntax/html.vim
+  unlet b:current_syntax
+  syn region odocTargetSpecific matchgroup=odocMarker start="{%html:" end="%}" contains=@odocHtml
+else
+  syn region odocTargetSpecific matchgroup=odocMarker start="{%html:" end="%}" contains=@Spell
+endif
+
+syn region odocDyckWord contained start="{" end="}" contains=odocDyckWord
+syn region odocTargetSpecific matchgroup=odocMarker start="{m\%(ath\)\?\>" end="}" contains=odocDyckWord
+syn region odocTargetSpecific matchgroup=odocMarker start="{%\%(latex\|texi\|man\):" end="%}" contains=@Spell
+syn region odocHeading start="{[0-5]" end="}" contains=@Spell
+syn region odocTable matchgroup=odocMarker start="{t\>" end="}" contains=@Spell,@odocInline
+syn region odocTable matchgroup=odocMarker start="{table\>" end="}" contains=odocTableRow
+syn region odocTableRow matchgroup=odocMarker start="{tr\>"  end="}" contains=odocTableEntry
+syn region odocTableEntry matchgroup=odocMarker start="{t[dh]\>"  end="}" contains=@Spell,@odocInline
+syn region odocCode matchgroup=odocMarker start="\[" end="\]"
+syn region odocCodeBlock matchgroup=odocMarker start="{@[^\[]\+\[" end="\]}"
+syn region odocCodeBlock matchgroup=odocMarker start="{\%(@ocaml\%(\s[^\[]*\)\?\)\?\[" end="\]}" contains=@odocSyntaxOCaml
+syn match odocListMarker "^\s*[-+]\s"
+syn region odocListItem contained matchgroup=odocListMarker start="{\%(-\|li\>\)" end="}" contains=@Spell,@odocInline
+syn region odocList matchgroup=odocListMarker start="{[ou]l\>" end="}" contains=odocListItem
+" a bit leniant with ":"
+syn match odocCrossrefKw contained "\<\%(module\%(-type\)\?\|class\%(-type\)\?\|val\|type\|exception\|method\|constructor\|extension\|field\|instance-variable\|section\|page\)[-:]"
+syn region odocCrossref start="{!" end="}" contains=odocCrossrefKw
+syn match odocTag "@\%(author\|deprecated\|param\|raise\|return\|see\|since\|before\|version\)"
+
+" Shamelessly borrowed from HTML syntax
+hi def odocBold     term=bold cterm=bold gui=bold
+hi def odocEmphasis term=bold,underline cterm=bold,underline gui=bold,underline
+hi def odocItalic   term=italic cterm=italic gui=italic
+
+hi def link odocCrossref Float
+hi def link odocCrossrefKw Keyword
+hi def link odocHeading Title
+hi def link odocLink Underlined
+hi def link odocListMarker Operator
+hi def link odocMarker Delimiter
+hi def link odocTag Keyword
+
+let b:current_syntax = "odoc"
+
+unlet odoc_syntax_loading
+
+let &cpo = s:keepcpo
+unlet s:keepcpo
+
+" vim: ts=8