new file mode 100644
--- /dev/null
+++ b/runtime/syntax/sml.vim
@@ -0,0 +1,230 @@
+" Vim syntax file
+" Language:     SML
+" Filenames:    *.sml *.sig
+" Maintainers:	Markus Mottl		<markus@oefai.at>
+"		Fabrizio Zeno Cornelli	<zeno@filibusta.crema.unimi.it>
+" URL:		http://www.ai.univie.ac.at/~markus/vim/syntax/sml.vim
+" Last Change:	2003 May 11
+"		2001 Nov 20 - Fixed small highlighting bug with modules (MM)
+"		2001 Aug 29 - Fixed small highlighting bug  (MM)
+
+" For version 5.x: Clear all syntax items
+" For version 6.x: Quit when a syntax file was already loaded
+if version < 600
+  syntax clear
+elseif exists("b:current_syntax")
+  finish
+endif
+
+" SML is case sensitive.
+syn case match
+
+" lowercase identifier - the standard way to match
+syn match    smlLCIdentifier /\<\(\l\|_\)\(\w\|'\)*\>/
+
+syn match    smlKeyChar    "|"
+
+" Errors
+syn match    smlBraceErr   "}"
+syn match    smlBrackErr   "\]"
+syn match    smlParenErr   ")"
+syn match    smlCommentErr "\*)"
+syn match    smlThenErr    "\<then\>"
+
+" Error-highlighting of "end" without synchronization:
+" as keyword or as error (default)
+if exists("sml_noend_error")
+  syn match    smlKeyword    "\<end\>"
+else
+  syn match    smlEndErr     "\<end\>"
+endif
+
+" Some convenient clusters
+syn cluster  smlAllErrs contains=smlBraceErr,smlBrackErr,smlParenErr,smlCommentErr,smlEndErr,smlThenErr
+
+syn cluster  smlAENoParen contains=smlBraceErr,smlBrackErr,smlCommentErr,smlEndErr,smlThenErr
+
+syn cluster  smlContained contains=smlTodo,smlPreDef,smlModParam,smlModParam1,smlPreMPRestr,smlMPRestr,smlMPRestr1,smlMPRestr2,smlMPRestr3,smlModRHS,smlFuncWith,smlFuncStruct,smlModTypeRestr,smlModTRWith,smlWith,smlWithRest,smlModType,smlFullMod
+
+
+" Enclosing delimiters
+syn region   smlEncl transparent matchgroup=smlKeyword start="(" matchgroup=smlKeyword end=")" contains=ALLBUT,@smlContained,smlParenErr
+syn region   smlEncl transparent matchgroup=smlKeyword start="{" matchgroup=smlKeyword end="}"  contains=ALLBUT,@smlContained,smlBraceErr
+syn region   smlEncl transparent matchgroup=smlKeyword start="\[" matchgroup=smlKeyword end="\]" contains=ALLBUT,@smlContained,smlBrackErr
+syn region   smlEncl transparent matchgroup=smlKeyword start="#\[" matchgroup=smlKeyword end="\]" contains=ALLBUT,@smlContained,smlBrackErr
+
+
+" Comments
+syn region   smlComment start="(\*" end="\*)" contains=smlComment,smlTodo
+syn keyword  smlTodo contained TODO FIXME XXX
+
+
+" let
+syn region   smlEnd matchgroup=smlKeyword start="\<let\>" matchgroup=smlKeyword end="\<end\>" contains=ALLBUT,@smlContained,smlEndErr
+
+" local
+syn region   smlEnd matchgroup=smlKeyword start="\<local\>" matchgroup=smlKeyword end="\<end\>" contains=ALLBUT,@smlContained,smlEndErr
+
+" abstype
+syn region   smlNone matchgroup=smlKeyword start="\<abstype\>" matchgroup=smlKeyword end="\<end\>" contains=ALLBUT,@smlContained,smlEndErr
+
+" begin
+syn region   smlEnd matchgroup=smlKeyword start="\<begin\>" matchgroup=smlKeyword end="\<end\>" contains=ALLBUT,@smlContained,smlEndErr
+
+" if
+syn region   smlNone matchgroup=smlKeyword start="\<if\>" matchgroup=smlKeyword end="\<then\>" contains=ALLBUT,@smlContained,smlThenErr
+
+
+"" Modules
+
+" "struct"
+syn region   smlStruct matchgroup=smlModule start="\<struct\>" matchgroup=smlModule end="\<end\>" contains=ALLBUT,@smlContained,smlEndErr
+
+" "sig"
+syn region   smlSig matchgroup=smlModule start="\<sig\>" matchgroup=smlModule end="\<end\>" contains=ALLBUT,@smlContained,smlEndErr,smlModule
+syn region   smlModSpec matchgroup=smlKeyword start="\<structure\>" matchgroup=smlModule end="\<\u\(\w\|'\)*\>" contained contains=@smlAllErrs,smlComment skipwhite skipempty nextgroup=smlModTRWith,smlMPRestr
+
+" "open"
+syn region   smlNone matchgroup=smlKeyword start="\<open\>" matchgroup=smlModule end="\<\u\(\w\|'\)*\(\.\u\(\w\|'\)*\)*\>" contains=@smlAllErrs,smlComment
+
+" "structure" - somewhat complicated stuff ;-)
+syn region   smlModule matchgroup=smlKeyword start="\<\(structure\|functor\)\>" matchgroup=smlModule end="\<\u\(\w\|'\)*\>" contains=@smlAllErrs,smlComment skipwhite skipempty nextgroup=smlPreDef
+syn region   smlPreDef start="."me=e-1 matchgroup=smlKeyword end="\l\|="me=e-1 contained contains=@smlAllErrs,smlComment,smlModParam,smlModTypeRestr,smlModTRWith nextgroup=smlModPreRHS
+syn region   smlModParam start="([^*]" end=")" contained contains=@smlAENoParen,smlModParam1
+syn match    smlModParam1 "\<\u\(\w\|'\)*\>" contained skipwhite skipempty nextgroup=smlPreMPRestr
+
+syn region   smlPreMPRestr start="."me=e-1 end=")"me=e-1 contained contains=@smlAllErrs,smlComment,smlMPRestr,smlModTypeRestr
+
+syn region   smlMPRestr start=":" end="."me=e-1 contained contains=@smlComment skipwhite skipempty nextgroup=smlMPRestr1,smlMPRestr2,smlMPRestr3
+syn region   smlMPRestr1 matchgroup=smlModule start="\ssig\s\=" matchgroup=smlModule end="\<end\>" contained contains=ALLBUT,@smlContained,smlEndErr,smlModule
+syn region   smlMPRestr2 start="\sfunctor\(\s\|(\)\="me=e-1 matchgroup=smlKeyword end="->" contained contains=@smlAllErrs,smlComment,smlModParam skipwhite skipempty nextgroup=smlFuncWith
+syn match    smlMPRestr3 "\w\(\w\|'\)*\(\.\w\(\w\|'\)*\)*" contained
+syn match    smlModPreRHS "=" contained skipwhite skipempty nextgroup=smlModParam,smlFullMod
+syn region   smlModRHS start="." end=".\w\|([^*]"me=e-2 contained contains=smlComment skipwhite skipempty nextgroup=smlModParam,smlFullMod
+syn match    smlFullMod "\<\u\(\w\|'\)*\(\.\u\(\w\|'\)*\)*" contained skipwhite skipempty nextgroup=smlFuncWith
+
+syn region   smlFuncWith start="([^*]"me=e-1 end=")" contained contains=smlComment,smlWith,smlFuncStruct
+syn region   smlFuncStruct matchgroup=smlModule start="[^a-zA-Z]struct\>"hs=s+1 matchgroup=smlModule end="\<end\>" contains=ALLBUT,@smlContained,smlEndErr
+
+syn match    smlModTypeRestr "\<\w\(\w\|'\)*\(\.\w\(\w\|'\)*\)*\>" contained
+syn region   smlModTRWith start=":\s*("hs=s+1 end=")" contained contains=@smlAENoParen,smlWith
+syn match    smlWith "\<\(\u\(\w\|'\)*\.\)*\w\(\w\|'\)*\>" contained skipwhite skipempty nextgroup=smlWithRest
+syn region   smlWithRest start="[^)]" end=")"me=e-1 contained contains=ALLBUT,@smlContained
+
+" "signature"
+syn region   smlKeyword start="\<signature\>" matchgroup=smlModule end="\<\w\(\w\|'\)*\>" contains=smlComment skipwhite skipempty nextgroup=smlMTDef
+syn match    smlMTDef "=\s*\w\(\w\|'\)*\>"hs=s+1,me=s
+
+syn keyword  smlKeyword  and andalso case
+syn keyword  smlKeyword  datatype else eqtype
+syn keyword  smlKeyword  exception fn fun handle
+syn keyword  smlKeyword  in infix infixl infixr
+syn keyword  smlKeyword  match nonfix of orelse
+syn keyword  smlKeyword  raise handle type
+syn keyword  smlKeyword  val where while with withtype
+
+syn keyword  smlType     bool char exn int list option
+syn keyword  smlType     real string unit
+
+syn keyword  smlOperator div mod not or quot rem
+
+syn keyword  smlBoolean      true false
+syn match    smlConstructor  "(\s*)"
+syn match    smlConstructor  "\[\s*\]"
+syn match    smlConstructor  "#\[\s*\]"
+syn match    smlConstructor  "\u\(\w\|'\)*\>"
+
+" Module prefix
+syn match    smlModPath      "\u\(\w\|'\)*\."he=e-1
+
+syn match    smlCharacter    +#"."\|#"\\\d\d\d"+
+syn match    smlCharErr      +#"\\\d\d"\|#"\\\d"+
+syn region   smlString       start=+"+ skip=+\\\\\|\\"+ end=+"+
+
+syn match    smlFunDef       "=>"
+syn match    smlRefAssign    ":="
+syn match    smlTopStop      ";;"
+syn match    smlOperator     "\^"
+syn match    smlOperator     "::"
+syn match    smlAnyVar       "\<_\>"
+syn match    smlKeyChar      "!"
+syn match    smlKeyChar      ";"
+syn match    smlKeyChar      "\*"
+syn match    smlKeyChar      "="
+
+syn match    smlNumber	      "\<-\=\d\+\>"
+syn match    smlNumber	      "\<-\=0[x|X]\x\+\>"
+syn match    smlReal	      "\<-\=\d\+\.\d*\([eE][-+]\=\d\+\)\=[fl]\=\>"
+
+" Synchronization
+syn sync minlines=20
+syn sync maxlines=500
+
+syn sync match smlEndSync     grouphere  smlEnd     "\<begin\>"
+syn sync match smlEndSync     groupthere smlEnd     "\<end\>"
+syn sync match smlStructSync  grouphere  smlStruct  "\<struct\>"
+syn sync match smlStructSync  groupthere smlStruct  "\<end\>"
+syn sync match smlSigSync     grouphere  smlSig     "\<sig\>"
+syn sync match smlSigSync     groupthere smlSig     "\<end\>"
+
+" Define the default highlighting.
+" For version 5.7 and earlier: only when not done already
+" For version 5.8 and later: only when an item doesn't have highlighting yet
+if version >= 508 || !exists("did_sml_syntax_inits")
+  if version < 508
+    let did_sml_syntax_inits = 1
+    command -nargs=+ HiLink hi link <args>
+  else
+    command -nargs=+ HiLink hi def link <args>
+  endif
+
+  HiLink smlBraceErr	 Error
+  HiLink smlBrackErr	 Error
+  HiLink smlParenErr	 Error
+
+  HiLink smlCommentErr	 Error
+
+  HiLink smlEndErr	 Error
+  HiLink smlThenErr	 Error
+
+  HiLink smlCharErr	 Error
+
+  HiLink smlComment	 Comment
+
+  HiLink smlModPath	 Include
+  HiLink smlModule	 Include
+  HiLink smlModParam1	 Include
+  HiLink smlModType	 Include
+  HiLink smlMPRestr3	 Include
+  HiLink smlFullMod	 Include
+  HiLink smlModTypeRestr Include
+  HiLink smlWith	 Include
+  HiLink smlMTDef	 Include
+
+  HiLink smlConstructor  Constant
+
+  HiLink smlModPreRHS	 Keyword
+  HiLink smlMPRestr2	 Keyword
+  HiLink smlKeyword	 Keyword
+  HiLink smlFunDef	 Keyword
+  HiLink smlRefAssign	 Keyword
+  HiLink smlKeyChar	 Keyword
+  HiLink smlAnyVar	 Keyword
+  HiLink smlTopStop	 Keyword
+  HiLink smlOperator	 Keyword
+
+  HiLink smlBoolean	 Boolean
+  HiLink smlCharacter	 Character
+  HiLink smlNumber	 Number
+  HiLink smlReal	 Float
+  HiLink smlString	 String
+  HiLink smlType	 Type
+  HiLink smlTodo	 Todo
+  HiLink smlEncl	 Keyword
+
+  delcommand HiLink
+endif
+
+let b:current_syntax = "sml"
+
+" vim: ts=8