diff --git a/runtime/syntax/ruby.vim b/runtime/syntax/ruby.vim
index 8b88378..0de63d0 100644
--- a/runtime/syntax/ruby.vim
+++ b/runtime/syntax/ruby.vim
@@ -3,7 +3,7 @@
 " Maintainer:		Doug Kearns <dougkearns@gmail.com>
 " URL:			https://github.com/vim-ruby/vim-ruby
 " Release Coordinator:	Doug Kearns <dougkearns@gmail.com>
-" Last Change:		2018 Jul 09
+" Last Change:		2019 Jul 13
 " ----------------------------------------------------------------------------
 "
 " Previous Maintainer:	Mirko Nasato
@@ -19,6 +19,11 @@
 let s:cpo_sav = &cpo
 set cpo&vim
 
+" eRuby Config {{{1
+if exists('main_syntax') && main_syntax == 'eruby'
+  let b:ruby_no_expensive = 1
+endif
+
 " Folding Config {{{1
 if has("folding") && exists("ruby_fold")
   setlocal foldmethod=syntax
@@ -33,6 +38,10 @@
       \	)
 
 function! s:foldable(...) abort
+  if index(s:foldable_groups, 'NONE') > -1
+    return 0
+  endif
+
   if index(s:foldable_groups, 'ALL') > -1
     return 1
   endif
@@ -44,9 +53,20 @@
   endfor
 
   return 0
-endfunction " }}}
+endfunction
 
-syn cluster rubyNotTop contains=@rubyExtendedStringSpecial,@rubyRegexpSpecial,@rubyDeclaration,rubyConditional,rubyExceptional,rubyMethodExceptional,rubyTodo,rubyModuleName,rubyClassName,rubySymbolDelimiter
+function! s:run_syntax_fold(args) abort
+  let [_0, _1, groups, cmd; _] = matchlist(a:args, '\(["'']\)\(.\{-}\)\1\s\+\(.*\)')
+  if call('s:foldable', split(groups))
+    let cmd .= ' fold'
+  endif
+  exe cmd
+endfunction
+
+com! -nargs=* SynFold call s:run_syntax_fold(<q-args>)
+
+" Not-Top Cluster {{{1
+syn cluster rubyNotTop contains=@rubyCommentNotTop,@rubyStringNotTop,@rubyRegexpSpecial,@rubyDeclaration,@rubyExceptionHandler,@rubyClassOperator,rubyConditional,rubyModuleName,rubyClassName,rubySymbolDelimiter,rubyParentheses
 
 " Whitespace Errors {{{1
 if exists("ruby_space_errors")
@@ -59,427 +79,400 @@
 endif
 
 " Operators {{{1
-if exists("ruby_operators")
-  syn match  rubyOperator "[~!^|*/%+-]\|&\.\@!\|\%(class\s*\)\@<!<<\|<=>\|<=\|\%(<\|\<class\s\+\u\w*\s*\)\@<!<[^<]\@=\|===\|==\|=\~\|>>\|>=\|=\@1<!>\|\*\*\|\.\.\.\|\.\.\|::"
-  syn match  rubyOperator "->\|-=\|/=\|\*\*=\|\*=\|&&=\|&=\|&&\|||=\||=\|||\|%=\|+=\|!\~\|!="
-  syn region rubyBracketOperator matchgroup=rubyOperator start="\%(\w[?!]\=\|[]})]\)\@2<=\[\s*" end="\s*]" contains=ALLBUT,@rubyNotTop
+
+syn match rubyEnglishBooleanOperator "\<\%(and\|or\|not\)\>"
+
+if exists("ruby_operators") || exists("ruby_pseudo_operators")
+  syn match rubyDotOperator	   "\.\|&\."
+
+  syn match rubyTernaryOperator    "\%(\w\|[^\x00-\x7F]\)\@1<!?\|:"
+  syn match rubyArithmeticOperator "\*\*\|[*/%+]\|->\@!"
+  syn match rubyComparisonOperator "<=>\|<=\|<\|>=\|[-=]\@1<!>"
+  syn match rubyBitwiseOperator    "[~^|]\|&\.\@!\|<<\|>>"
+  syn match rubyBooleanOperator    "\%(\w\|[^\x00-\x7F]\)\@1<!!\|&&\|||"
+  syn match rubyRangeOperator	   "\.\.\.\="
+  syn match rubyAssignmentOperator "=>\@!\|-=\|/=\|\*\*=\|\*=\|&&=\|&=\|||=\||=\|%=\|+=\|>>=\|<<=\|\^="
+  syn match rubyAssignmentOperator "=>\@!" containedin=rubyBlockParameterList " TODO: this is inelegant
+  syn match rubyEqualityOperator   "===\|==\|!=\|!\~\|=\~"
+
+  syn region rubyBracketOperator matchgroup=rubyOperator start="\%(\%(\w\|[^\x00-\x7F]\)[?!]\=\|[]})]\)\@2<=\[" end="]" contains=ALLBUT,@rubyNotTop
+
+  syn match rubyScopeOperator	    "::"
+  syn match rubySuperClassOperator  "<"	 contained
+  syn match rubyEigenClassOperator  "<<" contained
+  syn match rubyLambdaOperator	    "->"
+  syn match rubySplatOperator	    "\%([[{(|,=]\_s*\)\@<=\*"
+  syn match rubySplatOperator	    "\%(^\|\s\)\@1<=\*\%(\h\|[^\x00-\x7F]\|[:$@[]\)\@="
+  syn match rubyDoubleSplatOperator "\%([{(|,]\_s*\)\@<=\*\*"
+  syn match rubyDoubleSplatOperator "\s\@1<=\*\*\%(\h\|[^\x00-\x7F]\|[:$@{]\)\@="
+  syn match rubyProcOperator	    "\%([[(|,]\_s*\)\@<=&"
+  syn match rubyProcOperator	    "\s\@1<=&\%(\h\|[^\x00-\x7F]\|[:$@]\|->\)\@="
+
+  syn cluster rubyProperOperator contains=rubyTernaryOperator,rubyArithmeticOperator,rubyComparisonOperator,rubyBitwiseOperator,rubyBooleanOperator,rubyRangeOperator,rubyAssignmentOperator,rubyEqualityOperator,rubyDefinedOperator,rubyEnglishBooleanOperator
+  syn cluster rubyClassOperator  contains=rubyEigenClassOperator,rubySuperClassOperator
+  syn cluster rubyPseudoOperator contains=rubyDotOperator,rubyScopeOperator,rubyEigenClassOperator,rubySuperClassOperator,rubyLambdaOperator,rubySplatOperator,rubyDoubleSplatOperator,rubyProcOperator
+  syn cluster rubyOperator	 contains=ruby.*Operator
 endif
 
-" Expression Substitution and Backslash Notation {{{1
-syn match rubyStringEscape "\\\\\|\\[abefnrstv]\|\\\o\{1,3}\|\\x\x\{1,2}"						    contained display
-syn match rubyStringEscape "\%(\\M-\\C-\|\\C-\\M-\|\\M-\\c\|\\c\\M-\|\\c\|\\C-\|\\M-\)\%(\\\o\{1,3}\|\\x\x\{1,2}\|\\\=\S\)" contained display
-syn match rubyQuoteEscape  "\\[\\']"											    contained display
-
+" String Interpolation and Backslash Notation {{{1
 syn region rubyInterpolation	      matchgroup=rubyInterpolationDelimiter start="#{" end="}" contained contains=ALLBUT,@rubyNotTop
-syn match  rubyInterpolation	      "#\%(\$\|@@\=\)\w\+"    display contained contains=rubyInterpolationDelimiter,rubyInstanceVariable,rubyClassVariable,rubyGlobalVariable,rubyPredefinedVariable
-syn match  rubyInterpolationDelimiter "#\ze\%(\$\|@@\=\)\w\+" display contained
-syn match  rubyInterpolation	      "#\$\%(-\w\|\W\)"       display contained contains=rubyInterpolationDelimiter,rubyPredefinedVariable,rubyInvalidVariable
-syn match  rubyInterpolationDelimiter "#\ze\$\%(-\w\|\W\)"    display contained
-syn region rubyNoInterpolation	      start="\\#{" end="}"	      contained
-syn match  rubyNoInterpolation	      "\\#{"		      display contained
-syn match  rubyNoInterpolation	      "\\#\%(\$\|@@\=\)\w\+"  display contained
-syn match  rubyNoInterpolation	      "\\#\$\W"		      display contained
+syn match  rubyInterpolation	      "#\$\%(-\w\|[!$&"'*+,./0:;<>?@\`~_]\|\w\+\)" display contained contains=rubyInterpolationDelimiter,@rubyGlobalVariable
+syn match  rubyInterpolation	      "#@@\=\w\+"				   display contained contains=rubyInterpolationDelimiter,rubyInstanceVariable,rubyClassVariable
+syn match  rubyInterpolationDelimiter "#\ze[$@]"				   display contained
 
-syn match rubyDelimiterEscape	"\\[(<{\[)>}\]]" transparent display contained contains=NONE
+syn match rubyStringEscape "\\\_."											   contained display
+syn match rubyStringEscape "\\\o\{1,3}\|\\x\x\{1,2}"									   contained display
+syn match rubyStringEscape "\\u\%(\x\{4}\|{\x\{1,6}\%(\s\+\x\{1,6}\)*}\)"						   contained display
+syn match rubyStringEscape "\%(\\M-\\C-\|\\C-\\M-\|\\M-\\c\|\\c\\M-\|\\c\|\\C-\|\\M-\)\%(\\\o\{1,3}\|\\x\x\{1,2}\|\\\=.\)" contained display
+
+syn match rubyBackslashEscape "\\\\" contained display
+syn match rubyQuoteEscape     "\\'"  contained display
+syn match rubySpaceEscape     "\\ "  contained display
+
+syn match rubyParenthesisEscape	  "\\[()]"  contained display
+syn match rubyCurlyBraceEscape	  "\\[{}]"  contained display
+syn match rubyAngleBracketEscape  "\\[<>]"  contained display
+syn match rubySquareBracketEscape "\\[[\]]" contained display
 
 syn region rubyNestedParentheses    start="("  skip="\\\\\|\\)"  matchgroup=rubyString end=")"	transparent contained
 syn region rubyNestedCurlyBraces    start="{"  skip="\\\\\|\\}"  matchgroup=rubyString end="}"	transparent contained
 syn region rubyNestedAngleBrackets  start="<"  skip="\\\\\|\\>"  matchgroup=rubyString end=">"	transparent contained
 syn region rubyNestedSquareBrackets start="\[" skip="\\\\\|\\\]" matchgroup=rubyString end="\]"	transparent contained
 
+syn cluster rubySingleCharEscape contains=rubyBackslashEscape,rubyQuoteEscape,rubySpaceEscape,rubyParenthesisEscape,rubyCurlyBraceEscape,rubyAngleBracketEscape,rubySquareBracketEscape
+syn cluster rubyNestedBrackets	 contains=rubyNested.\+
+syn cluster rubyStringSpecial	 contains=rubyInterpolation,rubyStringEscape
+syn cluster rubyStringNotTop	 contains=@rubyStringSpecial,@rubyNestedBrackets,@rubySingleCharEscape
+
 " Regular Expression Metacharacters {{{1
-" These are mostly Oniguruma ready
-syn region rubyRegexpComment	matchgroup=rubyRegexpSpecial   start="(?#"								  skip="\\)"  end=")"  contained
-syn region rubyRegexpParens	matchgroup=rubyRegexpSpecial   start="(\(?:\|?<\=[=!]\|?>\|?<[a-z_]\w*>\|?[imx]*-[imx]*:\=\|\%(?#\)\@!\)" skip="\\)"  end=")"  contained transparent contains=@rubyRegexpSpecial
-syn region rubyRegexpBrackets	matchgroup=rubyRegexpCharClass start="\[\^\="								  skip="\\\]" end="\]" contained transparent contains=rubyStringEscape,rubyRegexpEscape,rubyRegexpCharClass oneline
-syn match  rubyRegexpCharClass	"\\[DdHhSsWw]"	       contained display
-syn match  rubyRegexpCharClass	"\[:\^\=\%(alnum\|alpha\|ascii\|blank\|cntrl\|digit\|graph\|lower\|print\|punct\|space\|upper\|xdigit\):\]" contained
-syn match  rubyRegexpEscape	"\\[].*?+^$|\\/(){}[]" contained
-syn match  rubyRegexpQuantifier	"[*?+][?+]\="	       contained display
-syn match  rubyRegexpQuantifier	"{\d\+\%(,\d*\)\=}?\=" contained display
-syn match  rubyRegexpAnchor	"[$^]\|\\[ABbGZz]"     contained display
-syn match  rubyRegexpDot	"\."		       contained display
-syn match  rubyRegexpSpecial	"|"		       contained display
-syn match  rubyRegexpSpecial	"\\[1-9]\d\=\d\@!"     contained display
-syn match  rubyRegexpSpecial	"\\k<\%([a-z_]\w*\|-\=\d\+\)\%([+-]\d\+\)\=>" contained display
-syn match  rubyRegexpSpecial	"\\k'\%([a-z_]\w*\|-\=\d\+\)\%([+-]\d\+\)\='" contained display
-syn match  rubyRegexpSpecial	"\\g<\%([a-z_]\w*\|-\=\d\+\)>" contained display
-syn match  rubyRegexpSpecial	"\\g'\%([a-z_]\w*\|-\=\d\+\)'" contained display
+syn region rubyRegexpComment	  matchgroup=rubyRegexpSpecial	 start="(?#"								    skip="\\\\\|\\)"  end=")"  contained
+syn region rubyRegexpParens	  matchgroup=rubyRegexpSpecial	 start="(\(?:\|?<\=[=!]\|?>\|?<[a-z_]\w*>\|?[imx]*-[imx]*:\=\|\%(?#\)\@!\)" skip="\\\\\|\\)"  end=")"  contained transparent contains=@rubyRegexpSpecial
+syn region rubyRegexpBrackets	  matchgroup=rubyRegexpCharClass start="\[\^\="								    skip="\\\\\|\\\]" end="\]" contained transparent contains=rubyRegexpBrackets,rubyStringEscape,rubyRegexpEscape,rubyRegexpCharClass,rubyRegexpIntersection oneline
+syn match  rubyRegexpCharClass	  "\\[DdHhRSsWw]"	 contained display
+syn match  rubyRegexpCharClass	  "\[:\^\=\%(alnum\|alpha\|ascii\|blank\|cntrl\|digit\|graph\|lower\|print\|punct\|space\|upper\|word\|xdigit\):\]" contained
+syn match  rubyRegexpCharClass	  "\\[pP]{^\=.\{-}}"	 contained display
+syn match  rubyRegexpEscape	  "\\[].*?+^$|\\/(){}[]" contained " see commit e477f10
+syn match  rubyRegexpQuantifier	  "[*?+][?+]\="		 contained display
+syn match  rubyRegexpQuantifier	  "{\d\+\%(,\d*\)\=}?\=" contained display
+syn match  rubyRegexpAnchor	  "[$^]\|\\[ABbGZz]"	 contained display
+syn match  rubyRegexpDot	  "\.\|\\X"		 contained display
+syn match  rubyRegexpIntersection "&&"			 contained display
+syn match  rubyRegexpSpecial	  "\\K"			 contained display
+syn match  rubyRegexpSpecial	  "|"			 contained display
+syn match  rubyRegexpSpecial	  "\\[1-9]\d\=\d\@!"	 contained display
+syn match  rubyRegexpSpecial	  "\\k<\%([a-z_]\w*\|-\=\d\+\)\%([+-]\d\+\)\=>" contained display
+syn match  rubyRegexpSpecial	  "\\k'\%([a-z_]\w*\|-\=\d\+\)\%([+-]\d\+\)\='" contained display
+syn match  rubyRegexpSpecial	  "\\g<\%([a-z_]\w*\|-\=\d\+\)>"		contained display
+syn match  rubyRegexpSpecial	  "\\g'\%([a-z_]\w*\|-\=\d\+\)'"		contained display
 
-syn cluster rubyStringSpecial	      contains=rubyInterpolation,rubyNoInterpolation,rubyStringEscape
-syn cluster rubyExtendedStringSpecial contains=@rubyStringSpecial,rubyNestedParentheses,rubyNestedCurlyBraces,rubyNestedAngleBrackets,rubyNestedSquareBrackets
-syn cluster rubyRegexpSpecial	      contains=rubyInterpolation,rubyNoInterpolation,rubyStringEscape,rubyRegexpSpecial,rubyRegexpEscape,rubyRegexpBrackets,rubyRegexpCharClass,rubyRegexpDot,rubyRegexpQuantifier,rubyRegexpAnchor,rubyRegexpParens,rubyRegexpComment
+syn cluster rubyRegexpSpecial contains=@rubyStringSpecial,rubyRegexpSpecial,rubyRegexpEscape,rubyRegexpBrackets,rubyRegexpCharClass,rubyRegexpDot,rubyRegexpQuantifier,rubyRegexpAnchor,rubyRegexpParens,rubyRegexpComment,rubyRegexpIntersection
 
-" Numbers and ASCII Codes {{{1
-syn match rubyASCIICode "\%(\w\|[]})\"'/]\)\@1<!\%(?\%(\\M-\\C-\|\\C-\\M-\|\\M-\\c\|\\c\\M-\|\\c\|\\C-\|\\M-\)\=\%(\\\o\{1,3}\|\\x\x\{1,2}\|\\\=\S\)\)"
-syn match rubyInteger	"\%(\%(\w\|[]})\"']\s*\)\@<!-\)\=\<0[xX]\x\+\%(_\x\+\)*r\=i\=\>"								display
-syn match rubyInteger	"\%(\%(\w\|[]})\"']\s*\)\@<!-\)\=\<\%(0[dD]\)\=\%(0\|[1-9]\d*\%(_\d\+\)*\)r\=i\=\>"						display
-syn match rubyInteger	"\%(\%(\w\|[]})\"']\s*\)\@<!-\)\=\<0[oO]\=\o\+\%(_\o\+\)*r\=i\=\>"								display
-syn match rubyInteger	"\%(\%(\w\|[]})\"']\s*\)\@<!-\)\=\<0[bB][01]\+\%(_[01]\+\)*r\=i\=\>"								display
-syn match rubyFloat	"\%(\%(\w\|[]})\"']\s*\)\@<!-\)\=\<\%(0\|[1-9]\d*\%(_\d\+\)*\)\.\d\+\%(_\d\+\)*r\=i\=\>"					display
-syn match rubyFloat	"\%(\%(\w\|[]})\"']\s*\)\@<!-\)\=\<\%(0\|[1-9]\d*\%(_\d\+\)*\)\%(\.\d\+\%(_\d\+\)*\)\=\%([eE][-+]\=\d\+\%(_\d\+\)*\)r\=i\=\>"	display
+" Numbers {{{1
+syn match rubyInteger "\%(\%(\w\|[^\x00-\x7F]\|[]})\"']\s*\)\@<!-\)\=\<0[xX]\x\+\%(_\x\+\)*r\=i\=\>"							       display
+syn match rubyInteger "\%(\%(\w\|[^\x00-\x7F]\|[]})\"']\s*\)\@<!-\)\=\<\%(0[dD]\)\=\%(0\|[1-9]\d*\%(_\d\+\)*\)r\=i\=\>"					       display
+syn match rubyInteger "\%(\%(\w\|[^\x00-\x7F]\|[]})\"']\s*\)\@<!-\)\=\<0[oO]\=\o\+\%(_\o\+\)*r\=i\=\>"							       display
+syn match rubyInteger "\%(\%(\w\|[^\x00-\x7F]\|[]})\"']\s*\)\@<!-\)\=\<0[bB][01]\+\%(_[01]\+\)*r\=i\=\>"						       display
+syn match rubyFloat   "\%(\%(\w\|[^\x00-\x7F]\|[]})\"']\s*\)\@<!-\)\=\<\%(0\|[1-9]\d*\%(_\d\+\)*\)\.\d\+\%(_\d\+\)*r\=i\=\>"				       display
+syn match rubyFloat   "\%(\%(\w\|[^\x00-\x7F]\|[]})\"']\s*\)\@<!-\)\=\<\%(0\|[1-9]\d*\%(_\d\+\)*\)\%(\.\d\+\%(_\d\+\)*\)\=\%([eE][-+]\=\d\+\%(_\d\+\)*\)i\=\>" display
 
 " Identifiers {{{1
-syn match rubyLocalVariableOrMethod "\<[_[:lower:]][_[:alnum:]]*[?!=]\=" contains=NONE display transparent
-syn match rubyBlockArgument	    "&[_[:lower:]][_[:alnum:]]"		 contains=NONE display transparent
+syn match rubyClassName	       "\%(\%(^\|[^.]\)\.\s*\)\@<!\<[[:upper:]]\%(\w\|[^\x00-\x7F]\)*\>\%(\s*(\)\@!" contained
+syn match rubyModuleName       "\%(\%(^\|[^.]\)\.\s*\)\@<!\<[[:upper:]]\%(\w\|[^\x00-\x7F]\)*\>\%(\s*(\)\@!" contained
+syn match rubyConstant	       "\%(\%(^\|[^.]\)\.\s*\)\@<!\<[[:upper:]]\%(\w\|[^\x00-\x7F]\)*\>\%(\s*(\)\@!"
+syn match rubyClassVariable    "@@\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*" display
+syn match rubyInstanceVariable "@\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*"  display
+syn match rubyGlobalVariable   "$\%(\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\|-.\)"
+syn match rubySymbolDelimiter  ":" contained
+syn match rubySymbol	       "[]})\"':]\@1<!:\%(\^\|\~@\|\~\|<<\|<=>\|<=\|<\|===\|[=!]=\|[=!]\~\|!@\|!\|>>\|>=\|>\||\|-@\|-\|/\|\[]=\|\[]\|\*\*\|\*\|&\|%\|+@\|+\|`\)" contains=rubySymbolDelimiter
+syn match rubySymbol	       "[]})\"':]\@1<!:\$\%(-.\|[`~<=>_,;:!?/.'"@$*\&+0]\)"			    contains=rubySymbolDelimiter
+syn match rubySymbol	       "[]})\"':]\@1<!:\%(\$\|@@\=\)\=\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*"  contains=rubySymbolDelimiter
+syn match rubySymbol	       "[]})\"':]\@1<!:\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\%([?!=]>\@!\)\=" contains=rubySymbolDelimiter
 
-syn match  rubyClassName	"\%(\%(^\|[^.]\)\.\s*\)\@<!\<\u\%(\w\|[^\x00-\x7F]\)*\>\%(\s*(\)\@!" contained
-syn match  rubyModuleName	"\%(\%(^\|[^.]\)\.\s*\)\@<!\<\u\%(\w\|[^\x00-\x7F]\)*\>\%(\s*(\)\@!" contained
-syn match  rubyConstant		"\%(\%(^\|[^.]\)\.\s*\)\@<!\<\u\%(\w\|[^\x00-\x7F]\)*\>\%(\s*(\)\@!"
-syn match  rubyClassVariable	"@@\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*" display
-syn match  rubyInstanceVariable "@\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*"	display
-syn match  rubyGlobalVariable	"$\%(\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\|-.\)"
-syn match  rubySymbolDelimiter	":" contained
-syn match  rubySymbol		"[]})\"':]\@1<!:\%(\^\|\~@\|\~\|<<\|<=>\|<=\|<\|===\|[=!]=\|[=!]\~\|!@\|!\|>>\|>=\|>\||\|-@\|-\|/\|\[]=\|\[]\|\*\*\|\*\|&\|%\|+@\|+\|`\)" contains=rubySymbolDelimiter
-syn match  rubySymbol		"[]})\"':]\@1<!:\$\%(-.\|[`~<=>_,;:!?/.'"@$*\&+0]\)" contains=rubySymbolDelimiter
-syn match  rubySymbol		"[]})\"':]\@1<!:\%(\$\|@@\=\)\=\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*" contains=rubySymbolDelimiter
-syn match  rubySymbol		"[]})\"':]\@1<!:\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\%([?!=]>\@!\)\=" contains=rubySymbolDelimiter
+SynFold ':' syn region rubySymbol matchgroup=rubySymbolDelimiter start="[]})\"':]\@1<!:'"  end="'"  skip="\\\\\|\\'"  contains=rubyQuoteEscape,rubyBackslashEscape
+SynFold ':' syn region rubySymbol matchgroup=rubySymbolDelimiter start="[]})\"':]\@1<!:\"" end="\"" skip="\\\\\|\\\"" contains=@rubyStringSpecial
 
-if s:foldable(':')
-  syn region rubySymbol		matchgroup=rubySymbolDelimiter start="[]})\"':]\@1<!:'"  end="'"  skip="\\\\\|\\'"  contains=rubyQuoteEscape fold
-  syn region rubySymbol		matchgroup=rubySymbolDelimiter start="[]})\"':]\@1<!:\"" end="\"" skip="\\\\\|\\\"" contains=@rubyStringSpecial fold
-else
-  syn region rubySymbol		matchgroup=rubySymbolDelimiter start="[]})\"':]\@1<!:'"  end="'"  skip="\\\\\|\\'"  contains=rubyQuoteEscape
-  syn region rubySymbol		matchgroup=rubySymbolDelimiter start="[]})\"':]\@1<!:\"" end="\"" skip="\\\\\|\\\"" contains=@rubyStringSpecial
+syn match rubyCapitalizedMethod "\%(\%(^\|[^.]\)\.\s*\)\@<!\<\u\%(\w\|[^\x00-\x7F]\)*\>\%(\s*(\)\@="
+
+syn region rubyParentheses	  start="("				 end=")" contains=ALLBUT,@rubyNotTop containedin=rubyBlockParameterList
+syn region rubyBlockParameterList start="\%(\%(\<do\>\|{\)\_s*\)\@32<=|" end="|" contains=ALLBUT,@rubyNotTop,@rubyProperOperator
+
+if exists('ruby_global_variable_error')
+  syn match rubyGlobalVariableError "$[^A-Za-z_]"	display
+  syn match rubyGlobalVariableError "$-[^0FIKWadilpvw]" display
 endif
 
-syn match  rubyCapitalizedMethod	"\%(\%(^\|[^.]\)\.\s*\)\@<!\<\u\%(\w\|[^\x00-\x7F]\)*\>\%(\s*(\)*\s*(\@="
-
-syn match  rubyBlockParameter	  "\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*" contained
-syn region rubyBlockParameterList start="\%(\%(\<do\>\|{\)\_s*\)\@32<=|" end="|" oneline display contains=rubyBlockParameter
-
-syn match rubyInvalidVariable	 "$[^ A-Za-z_-]"
-syn match rubyPredefinedVariable #$[!$&"'*+,./0:;<=>?@\`~]#
-syn match rubyPredefinedVariable "$\d\+"										   display
-syn match rubyPredefinedVariable "$_\>"											   display
-syn match rubyPredefinedVariable "$-[0FIKadilpvw]\>"									   display
-syn match rubyPredefinedVariable "$\%(deferr\|defout\|stderr\|stdin\|stdout\)\>"					   display
-syn match rubyPredefinedVariable "$\%(DEBUG\|FILENAME\|KCODE\|LOADED_FEATURES\|LOAD_PATH\|PROGRAM_NAME\|SAFE\|VERBOSE\)\>" display
-syn match rubyPredefinedConstant "\%(\%(^\|[^.]\)\.\s*\)\@<!\<\%(ARGF\|ARGV\|ENV\|DATA\|FALSE\|NIL\|STDERR\|STDIN\|STDOUT\|TOPLEVEL_BINDING\|TRUE\)\>\%(\s*(\)\@!"
+syn match rubyPredefinedVariable #$[!$&"'*+,./0:;<>?@\`~]#
+syn match rubyPredefinedVariable "$\d\+"									    display
+syn match rubyPredefinedVariable "$_\>"										    display
+syn match rubyPredefinedVariable "$-[0FIWadilpvw]\>"								    display
+syn match rubyPredefinedVariable "$\%(stderr\|stdin\|stdout\)\>"						    display
+syn match rubyPredefinedVariable "$\%(DEBUG\|FILENAME\|LOADED_FEATURES\|LOAD_PATH\|PROGRAM_NAME\|SAFE\|VERBOSE\)\>" display
+syn match rubyPredefinedConstant "\%(\%(^\|[^.]\)\.\s*\)\@<!\<\%(ARGF\|ARGV\|ENV\|DATA\|STDERR\|STDIN\|STDOUT\|TOPLEVEL_BINDING\)\>\%(\s*(\)\@!"
 syn match rubyPredefinedConstant "\%(\%(^\|[^.]\)\.\s*\)\@<!\<\%(RUBY_\%(VERSION\|RELEASE_DATE\|PLATFORM\|PATCHLEVEL\|REVISION\|DESCRIPTION\|COPYRIGHT\|ENGINE\)\)\>\%(\s*(\)\@!"
 
-" Normal Regular Expression {{{1
-if s:foldable('/')
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="\%(\%(^\|\<\%(and\|or\|while\|until\|unless\|if\|elsif\|when\|not\|then\|else\)\|[;\~=!|&(,{[<>?:*+-]\)\s*\)\@<=/" end="/[iomxneus]*" skip="\\\\\|\\/" contains=@rubyRegexpSpecial fold
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="\%(\h\k*\s\+\)\@<=/\%([ \t=]\|$\)\@!" end="/[iomxneus]*" skip="\\\\\|\\/" contains=@rubyRegexpSpecial fold
-else
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="\%(\%(^\|\<\%(and\|or\|while\|until\|unless\|if\|elsif\|when\|not\|then\|else\)\|[;\~=!|&(,{[<>?:*+-]\)\s*\)\@<=/" end="/[iomxneus]*" skip="\\\\\|\\/" contains=@rubyRegexpSpecial
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="\%(\h\k*\s\+\)\@<=/\%([ \t=]\|$\)\@!" end="/[iomxneus]*" skip="\\\\\|\\/" contains=@rubyRegexpSpecial
-endif
+" Deprecated/removed in 1.9
+syn match rubyPredefinedVariable "$="
+syn match rubyPredefinedVariable "$-K\>"		  display
+syn match rubyPredefinedVariable "$\%(deferr\|defout\)\>" display
+syn match rubyPredefinedVariable "$KCODE\>"		  display
+" Deprecated/removed in 2.4
+syn match rubyPredefinedConstant "\%(\%(^\|[^.]\)\.\s*\)\@<!\<\%(FALSE\|NIL\|TRUE\)\>\%(\s*(\)\@!"
 
-" Generalized Regular Expression {{{1
-if s:foldable('%')
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="%r\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1[iomxneus]*" skip="\\\\\|\\\z1" contains=@rubyRegexpSpecial fold
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="%r{"				end="}[iomxneus]*"   skip="\\\\\|\\}"	 contains=@rubyRegexpSpecial fold
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="%r<"				end=">[iomxneus]*"   skip="\\\\\|\\>"	 contains=@rubyRegexpSpecial,rubyNestedAngleBrackets,rubyDelimiterEscape fold
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="%r\["				end="\][iomxneus]*"  skip="\\\\\|\\\]"	 contains=@rubyRegexpSpecial fold
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="%r("				end=")[iomxneus]*"   skip="\\\\\|\\)"	 contains=@rubyRegexpSpecial fold
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="%r\z(\s\)"				end="\z1[iomxneus]*" skip="\\\\\|\\\z1" contains=@rubyRegexpSpecial fold
-else
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="%r\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1[iomxneus]*" skip="\\\\\|\\\z1" contains=@rubyRegexpSpecial
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="%r{"				end="}[iomxneus]*"   skip="\\\\\|\\}"	 contains=@rubyRegexpSpecial
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="%r<"				end=">[iomxneus]*"   skip="\\\\\|\\>"	 contains=@rubyRegexpSpecial,rubyNestedAngleBrackets,rubyDelimiterEscape
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="%r\["				end="\][iomxneus]*"  skip="\\\\\|\\\]"	 contains=@rubyRegexpSpecial
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="%r("				end=")[iomxneus]*"   skip="\\\\\|\\)"	 contains=@rubyRegexpSpecial
-  syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="%r\z(\s\)"				end="\z1[iomxneus]*" skip="\\\\\|\\\z1" contains=@rubyRegexpSpecial
-endif
+syn cluster rubyGlobalVariable contains=rubyGlobalVariable,rubyPredefinedVariable,rubyGlobalVariableError
 
-" Normal String {{{1
+" Normal Regular Expressions {{{1
+SynFold '/' syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="\%(\%(^\|\<\%(and\|or\|while\|until\|unless\|if\|elsif\|when\|not\|then\|else\)\|[;\~=!|&(,{[<>?:*+-]\)\s*\)\@<=/" end="/[iomxneus]*" skip="\\\\\|\\/" contains=@rubyRegexpSpecial nextgroup=@rubyModifier skipwhite
+SynFold '/' syn region rubyRegexp matchgroup=rubyRegexpDelimiter start="\%(\%(\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\)\s\+\)\@<=/\%(=\|\_s\)\@!"					   end="/[iomxneus]*" skip="\\\\\|\\/" contains=@rubyRegexpSpecial nextgroup=@rubyModifier skipwhite
+
+" Generalized Regular Expressions {{{1
+SynFold '%' syn region rubyRegexp matchgroup=rubyPercentRegexpDelimiter start="%r\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1[iomxneus]*" skip="\\\\\|\\\z1" contains=@rubyRegexpSpecial nextgroup=@rubyModifier skipwhite
+SynFold '%' syn region rubyRegexp matchgroup=rubyPercentRegexpDelimiter start="%r{"				   end="}[iomxneus]*"	skip="\\\\\|\\}"   contains=@rubyRegexpSpecial
+SynFold '%' syn region rubyRegexp matchgroup=rubyPercentRegexpDelimiter start="%r<"				   end=">[iomxneus]*"	skip="\\\\\|\\>"   contains=@rubyRegexpSpecial,rubyNestedAngleBrackets
+SynFold '%' syn region rubyRegexp matchgroup=rubyPercentRegexpDelimiter start="%r\["				   end="\][iomxneus]*"	skip="\\\\\|\\\]"  contains=@rubyRegexpSpecial
+SynFold '%' syn region rubyRegexp matchgroup=rubyPercentRegexpDelimiter start="%r("				   end=")[iomxneus]*"	skip="\\\\\|\\)"   contains=@rubyRegexpSpecial
+SynFold '%' syn region rubyRegexp matchgroup=rubyPercentRegexpDelimiter start="%r\z(\s\)"			   end="\z1[iomxneus]*" skip="\\\\\|\\\z1" contains=@rubyRegexpSpecial
+
+" Characters {{{1
+syn match rubyCharacter "\%(\w\|[^\x00-\x7F]\|[]})\"'/]\)\@1<!\%(?\%(\\M-\\C-\|\\C-\\M-\|\\M-\\c\|\\c\\M-\|\\c\|\\C-\|\\M-\)\=\%(\\\o\{1,3}\|\\x\x\{1,2}\|\\[[:space:]]\|\\\=[^[:space:]]\)\)"
+syn match rubyCharacter "\%(\w\|[^\x00-\x7F]\|[]})\"'/]\)\@1<!?\\u\%(\x\{4}\|{\x\{1,6}}\)"
+
+" Normal Strings {{{1
 let s:spell_cluster = exists('ruby_spellcheck_strings') ? ',@Spell' : ''
-exe 'syn region rubyString matchgroup=rubyStringDelimiter start="\"" end="\"" skip="\\\\\|\\\"" ' .
-      \ (s:foldable('%') ? 'fold' : '') . ' contains=@rubyStringSpecial' . s:spell_cluster
-exe 'syn region rubyString matchgroup=rubyStringDelimiter start="''" end="''" skip="\\\\\|\\''" ' .
-      \ (s:foldable('%') ? 'fold' : '') . ' contains=rubyQuoteEscape'	 . s:spell_cluster
+let s:fold_arg	    = s:foldable('string')		? ' fold'   : ''
+exe 'syn region rubyString matchgroup=rubyStringDelimiter start="\"" end="\"" skip="\\\\\|\\\""  contains=@rubyStringSpecial'		       . s:spell_cluster . s:fold_arg
+exe 'syn region rubyString matchgroup=rubyStringDelimiter start="''" end="''" skip="\\\\\|\\''"  contains=rubyQuoteEscape,rubyBackslashEscape' . s:spell_cluster . s:fold_arg
+unlet s:spell_cluster s:fold_arg
 
 " Shell Command Output {{{1
-if s:foldable('%')
-  syn region rubyString matchgroup=rubyStringDelimiter start="`" end="`" skip="\\\\\|\\`" contains=@rubyStringSpecial fold
-else
-  syn region rubyString matchgroup=rubyStringDelimiter start="`" end="`" skip="\\\\\|\\`" contains=@rubyStringSpecial
-endif
+SynFold 'string' syn region rubyString matchgroup=rubyStringDelimiter start="`" end="`" skip="\\\\\|\\`" contains=@rubyStringSpecial
 
-" Generalized Single Quoted String, Symbol and Array of Strings {{{1
-if s:foldable('%')
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[qw]\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1" skip="\\\\\|\\\z1" fold
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[qw]{"				     end="}"   skip="\\\\\|\\}"	  fold contains=rubyNestedCurlyBraces,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[qw]<"				     end=">"   skip="\\\\\|\\>"	  fold contains=rubyNestedAngleBrackets,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[qw]\["				     end="\]"  skip="\\\\\|\\\]"  fold contains=rubyNestedSquareBrackets,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[qw]("				     end=")"   skip="\\\\\|\\)"	  fold contains=rubyNestedParentheses,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%q\z(\s\)"			     end="\z1" skip="\\\\\|\\\z1" fold
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%s\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)"    end="\z1" skip="\\\\\|\\\z1" fold
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%s{"				     end="}"   skip="\\\\\|\\}"	  fold contains=rubyNestedCurlyBraces,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%s<"				     end=">"   skip="\\\\\|\\>"	  fold contains=rubyNestedAngleBrackets,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%s\["				     end="\]"  skip="\\\\\|\\\]"  fold contains=rubyNestedSquareBrackets,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%s("				     end=")"   skip="\\\\\|\\)"	  fold contains=rubyNestedParentheses,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%s\z(\s\)"			     end="\z1" skip="\\\\\|\\\z1" fold
-else
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[qw]\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1" skip="\\\\\|\\\z1"
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[qw]{"				     end="}"   skip="\\\\\|\\}"	  contains=rubyNestedCurlyBraces,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[qw]<"				     end=">"   skip="\\\\\|\\>"	  contains=rubyNestedAngleBrackets,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[qw]\["				     end="\]"  skip="\\\\\|\\\]"  contains=rubyNestedSquareBrackets,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[qw]("				     end=")"   skip="\\\\\|\\)"	  contains=rubyNestedParentheses,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%q\z(\s\)"			     end="\z1" skip="\\\\\|\\\z1"
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%s\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)"    end="\z1" skip="\\\\\|\\\z1"
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%s{"				     end="}"   skip="\\\\\|\\}"	  contains=rubyNestedCurlyBraces,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%s<"				     end=">"   skip="\\\\\|\\>"	  contains=rubyNestedAngleBrackets,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%s\["				     end="\]"  skip="\\\\\|\\\]"  contains=rubyNestedSquareBrackets,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%s("				     end=")"   skip="\\\\\|\\)"	  contains=rubyNestedParentheses,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%s\z(\s\)"			     end="\z1" skip="\\\\\|\\\z1"
-endif
+" Generalized Single Quoted Strings, Symbols, Array of Strings and Array of Symbols {{{1
 
-" Generalized Double Quoted String and Array of Strings and Shell Command Output {{{1
-" Note: %= is not matched here as the beginning of a double quoted string
-if s:foldable('%')
-  syn region rubyString matchgroup=rubyStringDelimiter start="%\z([~`!@#$%^&*_\-+|\:;"',.?/]\)"	      end="\z1" skip="\\\\\|\\\z1" contains=@rubyStringSpecial fold
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[QWx]\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1" skip="\\\\\|\\\z1" contains=@rubyStringSpecial fold
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[QWx]\={"			      end="}"	skip="\\\\\|\\}"   contains=@rubyStringSpecial,rubyNestedCurlyBraces,rubyDelimiterEscape    fold
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[QWx]\=<"			      end=">"	skip="\\\\\|\\>"   contains=@rubyStringSpecial,rubyNestedAngleBrackets,rubyDelimiterEscape  fold
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[QWx]\=\["			      end="\]"	skip="\\\\\|\\\]"  contains=@rubyStringSpecial,rubyNestedSquareBrackets,rubyDelimiterEscape fold
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[QWx]\=("			      end=")"	skip="\\\\\|\\)"   contains=@rubyStringSpecial,rubyNestedParentheses,rubyDelimiterEscape    fold
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[Qx]\z(\s\)"			      end="\z1" skip="\\\\\|\\\z1" contains=@rubyStringSpecial fold
-else
-  syn region rubyString matchgroup=rubyStringDelimiter start="%\z([~`!@#$%^&*_\-+|\:;"',.?/]\)"	      end="\z1" skip="\\\\\|\\\z1" contains=@rubyStringSpecial
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[QWx]\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1" skip="\\\\\|\\\z1" contains=@rubyStringSpecial
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[QWx]\={"			      end="}"	skip="\\\\\|\\}"   contains=@rubyStringSpecial,rubyNestedCurlyBraces,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[QWx]\=<"			      end=">"	skip="\\\\\|\\>"   contains=@rubyStringSpecial,rubyNestedAngleBrackets,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[QWx]\=\["			      end="\]"	skip="\\\\\|\\\]"  contains=@rubyStringSpecial,rubyNestedSquareBrackets,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[QWx]\=("			      end=")"	skip="\\\\\|\\)"   contains=@rubyStringSpecial,rubyNestedParentheses,rubyDelimiterEscape
-  syn region rubyString matchgroup=rubyStringDelimiter start="%[Qx]\z(\s\)"			      end="\z1" skip="\\\\\|\\\z1" contains=@rubyStringSpecial
-endif
+" Non-bracket punctuation delimiters {{{2
+let s:names = { '~': 'Tilde', '`': 'BackQuote', '!': 'Bang', '@': 'At', '#': 'Hash', '$': 'Dollar', '%': 'Percent', '^': 'Caret',
+      \		'&': 'Ampersand', '*': 'Asterix', '_': 'Underscore', '-': 'Dash', '+': 'Plus', '=': 'Equals', '|': 'Bar',
+      \		'\': 'Backslash', ':': 'Colon', ';': 'Semicolon', '"': 'DoubleQuote', "'": 'Quote', ',': 'Comma', '.': 'Period',
+      \		'?': 'QuestionMark', '/': 'ForwardSlash' }
 
-" Array of Symbols {{{1
-if s:foldable('%')
-  " Array of Symbols
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%i\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1" skip="\\\\\|\\\z1"	fold
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%i{"				  end="}"   skip="\\\\\|\\}"	fold contains=rubyNestedCurlyBraces,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%i<"				  end=">"   skip="\\\\\|\\>"	fold contains=rubyNestedAngleBrackets,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%i\["				  end="\]"  skip="\\\\\|\\\]"	fold contains=rubyNestedSquareBrackets,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%i("				  end=")"   skip="\\\\\|\\)"	fold contains=rubyNestedParentheses,rubyDelimiterEscape
+for s:delimiter in keys(s:names)
+  let s:group = 'ruby' . s:names[s:delimiter] . 'Escape'
 
-  " Array of interpolated Symbols
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%I\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1" skip="\\\\\|\\\z1"	contains=@rubyStringSpecial fold
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%I{"				  end="}"   skip="\\\\\|\\}"	contains=@rubyStringSpecial,rubyNestedCurlyBraces,rubyDelimiterEscape    fold
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%I<"				  end=">"   skip="\\\\\|\\>"	contains=@rubyStringSpecial,rubyNestedAngleBrackets,rubyDelimiterEscape  fold
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%I\["				  end="\]"  skip="\\\\\|\\\]"	contains=@rubyStringSpecial,rubyNestedSquareBrackets,rubyDelimiterEscape fold
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%I("				  end=")"   skip="\\\\\|\\)"	contains=@rubyStringSpecial,rubyNestedParentheses,rubyDelimiterEscape    fold
-else
-  " Array of Symbols
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%i\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1" skip="\\\\\|\\\z1"
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%i{"				  end="}"   skip="\\\\\|\\}"	contains=rubyNestedCurlyBraces,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%i<"				  end=">"   skip="\\\\\|\\>"	contains=rubyNestedAngleBrackets,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%i\["				  end="\]"  skip="\\\\\|\\\]"	contains=rubyNestedSquareBrackets,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%i("				  end=")"   skip="\\\\\|\\)"	contains=rubyNestedParentheses,rubyDelimiterEscape
+  if s:delimiter =~ '[\"]'
+    let s:delimiter = '\' . s:delimiter
+  endif
 
-  " Array of interpolated Symbols
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%I\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1" skip="\\\\\|\\\z1"	contains=@rubyStringSpecial
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%I{"				  end="}"   skip="\\\\\|\\}"	contains=@rubyStringSpecial,rubyNestedCurlyBraces,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%I<"				  end=">"   skip="\\\\\|\\>"	contains=@rubyStringSpecial,rubyNestedAngleBrackets,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%I\["				  end="\]"  skip="\\\\\|\\\]"	contains=@rubyStringSpecial,rubyNestedSquareBrackets,rubyDelimiterEscape
-  syn region rubySymbol matchgroup=rubySymbolDelimiter start="%I("				  end=")"   skip="\\\\\|\\)"	contains=@rubyStringSpecial,rubyNestedParentheses,rubyDelimiterEscape
-endif
+  exe 'syn match ' . s:group . ' "\V\\' . s:delimiter . '" contained display'
+  exe 'syn cluster rubySingleCharEscape add=' . s:group
+  exe 'SynFold ''%'' syn region rubyString matchgroup=rubyPercentStringDelimiter start="\V%q' . s:delimiter . '" end="\V' . s:delimiter . '" skip="\V\\\\\|\\' . s:delimiter . '" contains=rubyBackslashEscape,'		 . s:group . ' nextgroup=@rubyModifier skipwhite'
+  exe 'SynFold ''%'' syn region rubyString matchgroup=rubyPercentStringDelimiter start="\V%w' . s:delimiter . '" end="\V' . s:delimiter . '" skip="\V\\\\\|\\' . s:delimiter . '" contains=rubyBackslashEscape,rubySpaceEscape,' . s:group . ' nextgroup=@rubyModifier skipwhite'
+  exe 'SynFold ''%'' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="\V%s' . s:delimiter . '" end="\V' . s:delimiter . '" skip="\V\\\\\|\\' . s:delimiter . '" contains=rubyBackslashEscape,'		 . s:group . ' nextgroup=@rubyModifier skipwhite'
+  exe 'SynFold ''%'' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="\V%i' . s:delimiter . '" end="\V' . s:delimiter . '" skip="\V\\\\\|\\' . s:delimiter . '" contains=rubyBackslashEscape,rubySpaceEscape,' . s:group . ' nextgroup=@rubyModifier skipwhite'
+  exe 'hi def link ' . s:group . ' rubyStringEscape'
+endfor
 
-" Here Document {{{1
-syn region rubyHeredocStart matchgroup=rubyStringDelimiter start=+\%(\%(class\|::\)\_s*\|\%([]})"'.]\)\s\|\w\)\@<!<<[-~]\=\zs\%(\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\)+	 end=+$+ oneline contains=ALLBUT,@rubyNotTop
-syn region rubyHeredocStart matchgroup=rubyStringDelimiter start=+\%(\%(class\|::\)\_s*\|\%([]})"'.]\)\s\|\w\)\@<!<<[-~]\=\zs"\%([^"]*\)"+ end=+$+ oneline contains=ALLBUT,@rubyNotTop
-syn region rubyHeredocStart matchgroup=rubyStringDelimiter start=+\%(\%(class\|::\)\_s*\|\%([]})"'.]\)\s\|\w\)\@<!<<[-~]\=\zs'\%([^']*\)'+ end=+$+ oneline contains=ALLBUT,@rubyNotTop
-syn region rubyHeredocStart matchgroup=rubyStringDelimiter start=+\%(\%(class\|::\)\_s*\|\%([]})"'.]\)\s\|\w\)\@<!<<[-~]\=\zs`\%([^`]*\)`+ end=+$+ oneline contains=ALLBUT,@rubyNotTop
+unlet s:delimiter s:group s:names
+" }}}2
 
-if s:foldable('<<')
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]})"'.]\)\s\|\w\)\@<!<<\z(\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\)\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+2	matchgroup=rubyStringDelimiter end=+^\z1$+ contains=rubyHeredocStart,rubyHeredoc,@rubyStringSpecial fold keepend
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]})"'.]\)\s\|\w\)\@<!<<"\z([^"]*\)"\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+2	matchgroup=rubyStringDelimiter end=+^\z1$+ contains=rubyHeredocStart,rubyHeredoc,@rubyStringSpecial fold keepend
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]})"'.]\)\s\|\w\)\@<!<<'\z([^']*\)'\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+2	matchgroup=rubyStringDelimiter end=+^\z1$+ contains=rubyHeredocStart,rubyHeredoc		    fold keepend
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]})"'.]\)\s\|\w\)\@<!<<`\z([^`]*\)`\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+2	matchgroup=rubyStringDelimiter end=+^\z1$+ contains=rubyHeredocStart,rubyHeredoc,@rubyStringSpecial fold keepend
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%q{"	  end="}"   skip="\\\\\|\\}"   contains=rubyBackslashEscape,rubyCurlyBraceEscape,rubyNestedCurlyBraces
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%q<"	  end=">"   skip="\\\\\|\\>"   contains=rubyBackslashEscape,rubyAngleBracketEscape,rubyNestedAngleBrackets
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%q\["	  end="\]"  skip="\\\\\|\\\]"  contains=rubyBackslashEscape,rubySquareBracketEscape,rubyNestedSquareBrackets
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%q("	  end=")"   skip="\\\\\|\\)"   contains=rubyBackslashEscape,rubyParenthesisEscape,rubyNestedParentheses
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%q\z(\s\)" end="\z1" skip="\\\\\|\\\z1" contains=rubyBackslashEscape,rubySpaceEscape
 
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]}).]\)\s\|\w\)\@<!<<[-~]\z(\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\)\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+3    matchgroup=rubyStringDelimiter end=+^\s*\zs\z1$+ contains=rubyHeredocStart,@rubyStringSpecial fold keepend
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]}).]\)\s\|\w\)\@<!<<[-~]"\z([^"]*\)"\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+3  matchgroup=rubyStringDelimiter end=+^\s*\zs\z1$+ contains=rubyHeredocStart,@rubyStringSpecial fold keepend
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]}).]\)\s\|\w\)\@<!<<[-~]'\z([^']*\)'\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+3  matchgroup=rubyStringDelimiter end=+^\s*\zs\z1$+ contains=rubyHeredocStart		    fold keepend
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]}).]\)\s\|\w\)\@<!<<[-~]`\z([^`]*\)`\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+3  matchgroup=rubyStringDelimiter end=+^\s*\zs\z1$+ contains=rubyHeredocStart,@rubyStringSpecial fold keepend
-else
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]})"'.]\)\s\|\w\)\@<!<<\z(\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\)\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+2	matchgroup=rubyStringDelimiter end=+^\z1$+ contains=rubyHeredocStart,rubyHeredoc,@rubyStringSpecial keepend
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]})"'.]\)\s\|\w\)\@<!<<"\z([^"]*\)"\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+2	matchgroup=rubyStringDelimiter end=+^\z1$+ contains=rubyHeredocStart,rubyHeredoc,@rubyStringSpecial keepend
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]})"'.]\)\s\|\w\)\@<!<<'\z([^']*\)'\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+2	matchgroup=rubyStringDelimiter end=+^\z1$+ contains=rubyHeredocStart,rubyHeredoc		    keepend
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]})"'.]\)\s\|\w\)\@<!<<`\z([^`]*\)`\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+2	matchgroup=rubyStringDelimiter end=+^\z1$+ contains=rubyHeredocStart,rubyHeredoc,@rubyStringSpecial keepend
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%w{"	  end="}"   skip="\\\\\|\\}"   contains=rubyBackslashEscape,rubySpaceEscape,rubyCurlyBraceEscape,rubyNestedCurlyBraces
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%w<"	  end=">"   skip="\\\\\|\\>"   contains=rubyBackslashEscape,rubySpaceEscape,rubyAngleBracketEscape,rubyNestedAngleBrackets
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%w\["	  end="\]"  skip="\\\\\|\\\]"  contains=rubyBackslashEscape,rubySpaceEscape,rubySquareBracketEscape,rubyNestedSquareBrackets
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%w("	  end=")"   skip="\\\\\|\\)"   contains=rubyBackslashEscape,rubySpaceEscape,rubyParenthesisEscape,rubyNestedParentheses
 
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]}).]\)\s\|\w\)\@<!<<[-~]\z(\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\)\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+3    matchgroup=rubyStringDelimiter end=+^\s*\zs\z1$+ contains=rubyHeredocStart,@rubyStringSpecial keepend
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]}).]\)\s\|\w\)\@<!<<[-~]"\z([^"]*\)"\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+3  matchgroup=rubyStringDelimiter end=+^\s*\zs\z1$+ contains=rubyHeredocStart,@rubyStringSpecial keepend
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]}).]\)\s\|\w\)\@<!<<[-~]'\z([^']*\)'\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+3  matchgroup=rubyStringDelimiter end=+^\s*\zs\z1$+ contains=rubyHeredocStart		    keepend
-  syn region rubyString start=+\%(\%(class\|::\)\_s*\|\%([]}).]\)\s\|\w\)\@<!<<[-~]`\z([^`]*\)`\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+3  matchgroup=rubyStringDelimiter end=+^\s*\zs\z1$+ contains=rubyHeredocStart,@rubyStringSpecial keepend
-endif
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%s{"	  end="}"   skip="\\\\\|\\}"   contains=rubyBackslashEscape,rubyCurlyBraceEscape,rubyNestedCurlyBraces
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%s<"	  end=">"   skip="\\\\\|\\>"   contains=rubyBackslashEscape,rubyAngleBracketEscape,rubyNestedAngleBrackets
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%s\["	  end="\]"  skip="\\\\\|\\\]"  contains=rubyBackslashEscape,rubySquareBracketEscape,rubyNestedSquareBrackets
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%s("	  end=")"   skip="\\\\\|\\)"   contains=rubyBackslashEscape,rubyParenthesisEscape,rubyNestedParentheses
+SynFold '%' syn region rubyString matchgroup=rubyPercentSymbolDelimiter start="%s\z(\s\)" end="\z1" skip="\\\\\|\\\z1" contains=rubyBackslashEscape,rubySpaceEscape
 
-" eRuby Config {{{1
-if exists('main_syntax') && main_syntax == 'eruby'
-  let b:ruby_no_expensive = 1
-endif
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%i{"	  end="}"   skip="\\\\\|\\}"   contains=rubyBackslashEscape,rubySpaceEscape,rubyCurlyBraceEscape,rubyNestedCurlyBraces
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%i<"	  end=">"   skip="\\\\\|\\>"   contains=rubyBackslashEscape,rubySpaceEscape,rubyAngleBracketEscape,rubyNestedAngleBrackets
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%i\["	  end="\]"  skip="\\\\\|\\\]"  contains=rubyBackslashEscape,rubySpaceEscape,rubySquareBracketEscape,rubyNestedSquareBrackets
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%i("	  end=")"   skip="\\\\\|\\)"   contains=rubyBackslashEscape,rubySpaceEscape,rubyParenthesisEscape,rubyNestedParentheses
+
+" Generalized Double Quoted Strings, Array of Strings, Array of Symbols and Shell Command Output {{{1
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="\%(\%(\w\|[^\x00-\x7F]\|]\)\s*\)\@<!%=" end="="	 skip="\\\\\|\\="   contains=@rubyStringSpecial nextgroup=@rubyModifier skipwhite
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%\z([~`!@#$%^&*_\-+|\:;"',.?/]\)"       end="\z1" skip="\\\\\|\\\z1" contains=@rubyStringSpecial nextgroup=@rubyModifier skipwhite
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%[QWx]\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1" skip="\\\\\|\\\z1" contains=@rubyStringSpecial nextgroup=@rubyModifier skipwhite
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%[QWx]\={"			       end="}"	 skip="\\\\\|\\}"   contains=@rubyStringSpecial,rubyNestedCurlyBraces
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%[QWx]\=<"			       end=">"	 skip="\\\\\|\\>"   contains=@rubyStringSpecial,rubyNestedAngleBrackets
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%[QWx]\=\["			       end="\]"  skip="\\\\\|\\\]"  contains=@rubyStringSpecial,rubyNestedSquareBrackets
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%[QWx]\=("			       end=")"	 skip="\\\\\|\\)"   contains=@rubyStringSpecial,rubyNestedParentheses
+SynFold '%' syn region rubyString matchgroup=rubyPercentStringDelimiter start="%[Qx]\z(\s\)"			       end="\z1" skip="\\\\\|\\\z1" contains=@rubyStringSpecial
+
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%I\z([~`!@#$%^&*_\-+=|\:;"',.?/]\)" end="\z1" skip="\\\\\|\\\z1" contains=@rubyStringSpecial nextgroup=@rubyModifier skipwhite
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%I{"				   end="}"   skip="\\\\\|\\}"	contains=@rubyStringSpecial,rubyNestedCurlyBraces
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%I<"				   end=">"   skip="\\\\\|\\>"	contains=@rubyStringSpecial,rubyNestedAngleBrackets
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%I\["				   end="\]"  skip="\\\\\|\\\]"	contains=@rubyStringSpecial,rubyNestedSquareBrackets
+SynFold '%' syn region rubySymbol matchgroup=rubyPercentSymbolDelimiter start="%I("				   end=")"   skip="\\\\\|\\)"	contains=@rubyStringSpecial,rubyNestedParentheses
+
+" Here Documents {{{1
+syn region rubyHeredocStart matchgroup=rubyHeredocDelimiter start=+\%(\%(class\|::\|\.\@1<!\.\)\_s*\|\%([]})"'`]\)\s\|\w\)\@<!<<[-~]\=\zs\%(\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\)+ end=+$+ oneline contains=ALLBUT,@rubyNotTop
+
+syn region rubyHeredocStart matchgroup=rubyHeredocDelimiter start=+\%(\%(class\|::\|\.\@1<!\.\)\_s*\|\%([]})"'`]\)\s\|\w\)\@<!<<[-~]\=\zs"\%([^"]*\)"+					   end=+$+ oneline contains=ALLBUT,@rubyNotTop
+syn region rubyHeredocStart matchgroup=rubyHeredocDelimiter start=+\%(\%(class\|::\|\.\@1<!\.\)\_s*\|\%([]})"'`]\)\s\|\w\)\@<!<<[-~]\=\zs'\%([^']*\)'+					   end=+$+ oneline contains=ALLBUT,@rubyNotTop
+syn region rubyHeredocStart matchgroup=rubyHeredocDelimiter start=+\%(\%(class\|::\|\.\@1<!\.\)\_s*\|\%([]})"'`]\)\s\|\w\)\@<!<<[-~]\=\zs`\%([^`]*\)`+					   end=+$+ oneline contains=ALLBUT,@rubyNotTop
+
+SynFold '<<' syn region rubyString start=+\%(\%(class\|::\|\.\@1<!\.\)\_s*\|\%([]})"'`]\)\s\|\w\)\@<!<<\z(\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\)\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+2  matchgroup=rubyHeredocDelimiter end=+^\z1$+	contains=rubyHeredocStart,@rubyStringSpecial keepend
+SynFold '<<' syn region rubyString start=+\%(\%(class\|::\|\.\@1<!\.\)\_s*\|\%([]})"'`]\)\s\|\w\)\@<!<<"\z([^"]*\)"\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+2				      matchgroup=rubyHeredocDelimiter end=+^\z1$+	contains=rubyHeredocStart,@rubyStringSpecial keepend
+SynFold '<<' syn region rubyString start=+\%(\%(class\|::\|\.\@1<!\.\)\_s*\|\%([]})"'`]\)\s\|\w\)\@<!<<'\z([^']*\)'\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+2				      matchgroup=rubyHeredocDelimiter end=+^\z1$+	contains=rubyHeredocStart		     keepend
+SynFold '<<' syn region rubyString start=+\%(\%(class\|::\|\.\@1<!\.\)\_s*\|\%([]})"'`]\)\s\|\w\)\@<!<<`\z([^`]*\)`\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+2				      matchgroup=rubyHeredocDelimiter end=+^\z1$+	contains=rubyHeredocStart,@rubyStringSpecial keepend
+
+SynFold '<<' syn region rubyString start=+\%(\%(class\|::\|\.\@1<!\.\)\_s*\|\%([]})]\)\s\|\w\)\@<!<<[-~]\z(\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\)\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+3 matchgroup=rubyHeredocDelimiter end=+^\s*\zs\z1$+ contains=rubyHeredocStart,@rubyStringSpecial keepend
+SynFold '<<' syn region rubyString start=+\%(\%(class\|::\|\.\@1<!\.\)\_s*\|\%([]})]\)\s\|\w\)\@<!<<[-~]"\z([^"]*\)"\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+3				      matchgroup=rubyHeredocDelimiter end=+^\s*\zs\z1$+ contains=rubyHeredocStart,@rubyStringSpecial keepend
+SynFold '<<' syn region rubyString start=+\%(\%(class\|::\|\.\@1<!\.\)\_s*\|\%([]})]\)\s\|\w\)\@<!<<[-~]'\z([^']*\)'\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+3				      matchgroup=rubyHeredocDelimiter end=+^\s*\zs\z1$+ contains=rubyHeredocStart		     keepend
+SynFold '<<' syn region rubyString start=+\%(\%(class\|::\|\.\@1<!\.\)\_s*\|\%([]})]\)\s\|\w\)\@<!<<[-~]`\z([^`]*\)`\ze\%(.*<<[-~]\=['`"]\=\h\)\@!+hs=s+3				      matchgroup=rubyHeredocDelimiter end=+^\s*\zs\z1$+ contains=rubyHeredocStart,@rubyStringSpecial keepend
 
 " Module, Class, Method and Alias Declarations {{{1
-syn match  rubyAliasDeclaration    "[^[:space:];#.()]\+" contained contains=rubySymbol,rubyGlobalVariable,rubyPredefinedVariable nextgroup=rubyAliasDeclaration2 skipwhite
-syn match  rubyAliasDeclaration2   "[^[:space:];#.()]\+" contained contains=rubySymbol,rubyGlobalVariable,rubyPredefinedVariable
-syn match  rubyMethodDeclaration   "[^[:space:];#(]\+"	 contained contains=rubyConstant,rubyBoolean,rubyPseudoVariable,rubyInstanceVariable,rubyClassVariable,rubyGlobalVariable
-syn match  rubyClassDeclaration    "[^[:space:];#<]\+"	 contained contains=rubyClassName,rubyOperator
-syn match  rubyModuleDeclaration   "[^[:space:];#<]\+"	 contained contains=rubyModuleName,rubyOperator
-syn match  rubyMethodName "\<[_[:alpha:]][_[:alnum:]]*[?!=]\=[[:alnum:]_.:?!=]\@!" contained containedin=rubyMethodDeclaration
-syn match  rubyMethodName "\%(\s\|^\)\@1<=[_[:alpha:]][_[:alnum:]]*[?!=]\=\%(\s\|$\)\@=" contained containedin=rubyAliasDeclaration,rubyAliasDeclaration2
-syn match  rubyMethodName "\%([[:space:].]\|^\)\@2<=\%(\[\]=\=\|\*\*\|[-+!~]@\=\|[*/%|&^~]\|<<\|>>\|[<>]=\=\|<=>\|===\|[=!]=\|[=!]\~\|!\|`\)\%([[:space:];#(]\|$\)\@=" contained containedin=rubyAliasDeclaration,rubyAliasDeclaration2,rubyMethodDeclaration
+syn match rubyAliasDeclaration	"[^[:space:];#.()]\+" contained contains=rubySymbol,@rubyGlobalVariable nextgroup=rubyAliasDeclaration2 skipwhite
+syn match rubyAliasDeclaration2 "[^[:space:];#.()]\+" contained contains=rubySymbol,@rubyGlobalVariable
+syn match rubyMethodDeclaration "[^[:space:];#(]\+"   contained contains=rubyConstant,rubyBoolean,rubyPseudoVariable,rubyInstanceVariable,rubyClassVariable,rubyGlobalVariable
+syn match rubyClassDeclaration	"[^[:space:];#<]\+"   contained contains=rubyClassName,rubyScopeOperator nextgroup=rubySuperClassOperator skipwhite skipnl
+syn match rubyModuleDeclaration "[^[:space:];#<]\+"   contained contains=rubyModuleName,rubyScopeOperator
 
-syn cluster rubyDeclaration contains=rubyAliasDeclaration,rubyAliasDeclaration2,rubyMethodDeclaration,rubyModuleDeclaration,rubyClassDeclaration,rubyMethodName,rubyBlockParameter
+syn match rubyMethodName "\<\%([_[:alpha:]]\|[^\x00-\x7F]\)\%([_[:alnum:]]\|[^\x00-\x7F]\)*[?!=]\=\%([[:alnum:]_.:?!=]\|[^\x00-\x7F]\)\@!"			      contained containedin=rubyMethodDeclaration
+syn match rubyMethodName "\%(\s\|^\)\@1<=\%([_[:alpha:]]\|[^\x00-\x7F]\)\%([_[:alnum:]]\|[^\x00-\x7F]\)*[?!=]\=\%(\s\|$\)\@="					      contained containedin=rubyAliasDeclaration,rubyAliasDeclaration2
+syn match rubyMethodName "\%([[:space:].]\|^\)\@1<=\%(\[\]=\=\|\*\*\|[-+!~]@\=\|[*/%|&^~]\|<<\|>>\|[<>]=\=\|<=>\|===\|[=!]=\|[=!]\~\|!\|`\)\%([[:space:];#(]\|$\)\@=" contained containedin=rubyAliasDeclaration,rubyAliasDeclaration2,rubyMethodDeclaration
+
+syn cluster rubyDeclaration contains=rubyAliasDeclaration,rubyAliasDeclaration2,rubyMethodDeclaration,rubyModuleDeclaration,rubyClassDeclaration,rubyMethodName
 
 " Keywords {{{1
-" Note: the following keywords have already been defined:
-" begin case class def do end for if module unless until while
-syn match   rubyControl	       "\<\%(and\|break\|in\|next\|not\|or\|redo\|rescue\|retry\|return\)\>[?!]\@!"
-syn match   rubyOperator       "\<defined?" display
-syn match   rubyKeyword	       "\<\%(super\|yield\)\>[?!]\@!"
-syn match   rubyBoolean	       "\<\%(true\|false\)\>[?!]\@!"
-syn match   rubyPseudoVariable "\<\%(nil\|self\|__ENCODING__\|__dir__\|__FILE__\|__LINE__\|__callee__\|__method__\)\>[?!]\@!" " TODO: reorganise
-syn match   rubyBeginEnd       "\<\%(BEGIN\|END\)\>[?!]\@!"
+" TODO: reorganise
+syn match rubyControl	     "\%#=1\<\%(break\|in\|next\|redo\|retry\|return\)\>"
+syn match rubyKeyword	     "\%#=1\<\%(super\|yield\)\>"
+syn match rubyBoolean	     "\%#=1\<\%(true\|false\)\>[?!]\@!"
+syn match rubyPseudoVariable "\%#=1\<\(self\|nil\)\>[?!]\@!"
+syn match rubyPseudoVariable "\%#=1\<__\%(ENCODING\|dir\|FILE\|LINE\|callee\|method\)__\>"
+syn match rubyBeginEnd	     "\%#=1\<\%(BEGIN\|END\)\>"
 
 " Expensive Mode {{{1
 " Match 'end' with the appropriate opening keyword for syntax based folding
 " and special highlighting of module/class/method definitions
 if !exists("b:ruby_no_expensive") && !exists("ruby_no_expensive")
-  syn match  rubyDefine "\<alias\>"  nextgroup=rubyAliasDeclaration  skipwhite skipnl
-  syn match  rubyDefine "\<def\>"    nextgroup=rubyMethodDeclaration skipwhite skipnl
-  syn match  rubyDefine "\<undef\>"  nextgroup=rubyMethodName	     skipwhite skipnl
-  syn match  rubyClass	"\<class\>"  nextgroup=rubyClassDeclaration  skipwhite skipnl
-  syn match  rubyModule "\<module\>" nextgroup=rubyModuleDeclaration skipwhite skipnl
+  syn match rubyDefine "\<alias\>"  nextgroup=rubyAliasDeclaration			  skipwhite skipnl
+  syn match rubyDefine "\<def\>"    nextgroup=rubyMethodDeclaration			  skipwhite skipnl
+  syn match rubyDefine "\<undef\>"  nextgroup=rubyMethodName				  skipwhite skipnl
+  syn match rubyClass  "\<class\>"  nextgroup=rubyClassDeclaration,rubyEigenClassOperator skipwhite skipnl
+  syn match rubyModule "\<module\>" nextgroup=rubyModuleDeclaration			  skipwhite skipnl
 
-  if s:foldable('def')
-    syn region rubyMethodBlock start="\<def\>"	matchgroup=rubyDefine end="\%(\<def\_s\+\)\@<!\<end\>" contains=ALLBUT,@rubyNotTop fold
-  else
-    syn region rubyMethodBlock start="\<def\>"	matchgroup=rubyDefine end="\%(\<def\_s\+\)\@<!\<end\>" contains=ALLBUT,@rubyNotTop
-  endif
-
-  if s:foldable('class')
-    syn region rubyBlock start="\<class\>"	matchgroup=rubyClass end="\<end\>" contains=ALLBUT,@rubyNotTop fold
-  else
-    syn region rubyBlock start="\<class\>"	matchgroup=rubyClass end="\<end\>" contains=ALLBUT,@rubyNotTop
-  endif
-
-  if s:foldable('module')
-    syn region rubyBlock start="\<module\>" matchgroup=rubyModule end="\<end\>" contains=ALLBUT,@rubyNotTop fold
-  else
-    syn region rubyBlock start="\<module\>" matchgroup=rubyModule end="\<end\>" contains=ALLBUT,@rubyNotTop
-  endif
+  SynFold 'def'    syn region rubyMethodBlock start="\<def\>"	 matchgroup=rubyDefine skip="\<end:\|\%(\<def\_s\+\)\@<=end\>" end="\<end\>" contains=ALLBUT,@rubyNotTop
+  SynFold 'class'  syn region rubyClassBlock  start="\<class\>"  matchgroup=rubyClass  skip="\<end:"			       end="\<end\>" contains=ALLBUT,@rubyNotTop
+  SynFold 'module' syn region rubyModuleBlock start="\<module\>" matchgroup=rubyModule skip="\<end:"			       end="\<end\>" contains=ALLBUT,@rubyNotTop
 
   " modifiers
-  syn match rubyLineContinuation    "\\$" nextgroup=rubyConditionalModifier,rubyRepeatModifier skipwhite skipnl
+  syn match rubyLineContinuation    "\\$" nextgroup=@rubyModifier skipwhite skipnl
   syn match rubyConditionalModifier "\<\%(if\|unless\)\>"
   syn match rubyRepeatModifier	    "\<\%(while\|until\)\>"
+  syn match rubyRescueModifier	    "\<rescue\>"
 
-  if s:foldable('do')
-    syn region rubyDoBlock matchgroup=rubyControl start="\<do\>" end="\<end\>" contains=ALLBUT,@rubyNotTop fold
-  else
-    syn region rubyDoBlock matchgroup=rubyControl start="\<do\>" end="\<end\>" contains=ALLBUT,@rubyNotTop
-  endif
+  syn cluster rubyModifier contains=rubyConditionalModifier,rubyRepeatModifier,rubyRescueModifier
+
+  SynFold 'do' syn region rubyDoBlock matchgroup=rubyControl start="\<do\>" skip="\<end:" end="\<end\>" contains=ALLBUT,@rubyNotTop
 
   " curly bracket block or hash literal
-  if s:foldable('{')
-    syn region rubyCurlyBlock matchgroup=rubyCurlyBlockDelimiter start="{" end="}" contains=ALLBUT,@rubyNotTop fold
-  else
-    syn region rubyCurlyBlock matchgroup=rubyCurlyBlockDelimiter start="{" end="}" contains=ALLBUT,@rubyNotTop
-  endif
-
-  if s:foldable('[')
-    syn region rubyArrayLiteral	matchgroup=rubyArrayDelimiter start="\%(\w\|[\]})]\)\@<!\[" end="]" contains=ALLBUT,@rubyNotTop fold
-  endif
+  SynFold '{' syn region rubyCurlyBlock   matchgroup=rubyCurlyBlockDelimiter start="{"						    end="}" contains=ALLBUT,@rubyNotTop
+  SynFold '[' syn region rubyArrayLiteral matchgroup=rubyArrayDelimiter      start="\%(\%(\w\|[^\x00-\x7F]\)[?!]\=\|[]})]\)\@2<!\[" end="]" contains=ALLBUT,@rubyNotTop
 
   " statements without 'do'
-  if s:foldable('begin')
-    syn region rubyBlockExpression matchgroup=rubyControl start="\<begin\>" end="\<end\>" contains=ALLBUT,@rubyNotTop fold
-  else
-    syn region rubyBlockExpression matchgroup=rubyControl start="\<begin\>" end="\<end\>" contains=ALLBUT,@rubyNotTop
-  endif
+  SynFold 'begin' syn region rubyBlockExpression matchgroup=rubyControl     start="\<begin\>" skip="\<end:" end="\<end\>" contains=ALLBUT,@rubyNotTop
+  SynFold 'case'  syn region rubyCaseExpression  matchgroup=rubyConditional start="\<case\>"  skip="\<end:" end="\<end\>" contains=ALLBUT,@rubyNotTop
 
-  if s:foldable('case')
-    syn region rubyCaseExpression matchgroup=rubyConditional start="\<case\>" end="\<end\>" contains=ALLBUT,@rubyNotTop fold
-  else
-    syn region rubyCaseExpression matchgroup=rubyConditional start="\<case\>" end="\<end\>" contains=ALLBUT,@rubyNotTop
-  endif
+  SynFold 'if' syn region rubyConditionalExpression matchgroup=rubyConditional start="\%(\%(^\|\.\.\.\=\|[{:,;([<>~\*/%&^|+=-]\|\<then\s\|\%(\<\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\)\@<![?!]\)\s*\)\@<=\%(if\|unless\)\>" skip="\<end:" end="\<end\>" contains=ALLBUT,@rubyNotTop
 
-  if s:foldable('if')
-    syn region rubyConditionalExpression matchgroup=rubyConditional start="\%(\%(^\|\.\.\.\=\|[{:,;([<>~\*%&^|+=-]\|\%(\<[_[:lower:]][_[:alnum:]]*\)\@<![?!]\)\s*\)\@<=\%(if\|unless\)\>" end="\%(\%(\%(\.\@1<!\.\)\|::\)\s*\)\@<!\<end\>" contains=ALLBUT,@rubyNotTop fold
-  else
-    syn region rubyConditionalExpression matchgroup=rubyConditional start="\%(\%(^\|\.\.\.\=\|[{:,;([<>~\*%&^|+=-]\|\%(\<[_[:lower:]][_[:alnum:]]*\)\@<![?!]\)\s*\)\@<=\%(if\|unless\)\>" end="\%(\%(\%(\.\@1<!\.\)\|::\)\s*\)\@<!\<end\>" contains=ALLBUT,@rubyNotTop
-  endif
+  syn match rubyConditional "\<\%(then\|else\|when\)\>"	 contained containedin=rubyCaseExpression
+  syn match rubyConditional "\<\%(then\|else\|elsif\)\>" contained containedin=rubyConditionalExpression
 
-  syn match rubyConditional "\<\%(then\|else\|when\)\>[?!]\@!"	contained containedin=rubyCaseExpression
-  syn match rubyConditional "\<\%(then\|else\|elsif\)\>[?!]\@!" contained containedin=rubyConditionalExpression
-
-  syn match rubyExceptional	  "\<\%(\%(\%(;\|^\)\s*\)\@<=rescue\|else\|ensure\)\>[?!]\@!" contained containedin=rubyBlockExpression
-  syn match rubyMethodExceptional "\<\%(\%(\%(;\|^\)\s*\)\@<=rescue\|else\|ensure\)\>[?!]\@!" contained containedin=rubyMethodBlock
+  syn match   rubyExceptionHandler  "\<\%(\%(\%(;\|^\)\s*\)\@<=rescue\|else\|ensure\)\>" contained containedin=rubyBlockExpression,rubyDoBlock
+  syn match   rubyExceptionHandler2 "\<\%(\%(\%(;\|^\)\s*\)\@<=rescue\|else\|ensure\)\>" contained containedin=rubyModuleBlock,rubyClassBlock,rubyMethodBlock
+  syn cluster rubyExceptionHandler  contains=rubyExceptionHandler,rubyExceptionHandler2
 
   " statements with optional 'do'
-  syn region rubyOptionalDoLine   matchgroup=rubyRepeat start="\<for\>[?!]\@!" start="\%(\%(^\|\.\.\.\=\|[{:,;([<>~\*/%&^|+-]\|\%(\<[_[:lower:]][_[:alnum:]]*\)\@<![!=?]\)\s*\)\@<=\<\%(until\|while\)\>" matchgroup=rubyOptionalDo end="\%(\<do\>\)" end="\ze\%(;\|$\)" oneline contains=ALLBUT,@rubyNotTop
+  syn region rubyOptionalDoLine matchgroup=rubyRepeat start="\<for\>" start="\%(\%(^\|\.\.\.\=\|[{:,;([<>~\*/%&^|+=-]\|\%(\<\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\)\@<![!?]\)\s*\)\@<=\<\%(until\|while\)\>" matchgroup=rubyOptionalDo end="\<do\>" end="\ze\%(;\|$\)" oneline contains=ALLBUT,@rubyNotTop
 
-  if s:foldable('for')
-    syn region rubyRepeatExpression start="\<for\>[?!]\@!" start="\%(\%(^\|\.\.\.\=\|[{:,;([<>~\*/%&^|+-]\|\%(\<[_[:lower:]][_[:alnum:]]*\)\@<![!=?]\)\s*\)\@<=\<\%(until\|while\)\>" matchgroup=rubyRepeat end="\<end\>" contains=ALLBUT,@rubyNotTop nextgroup=rubyOptionalDoLine fold
-  else
-    syn region rubyRepeatExpression start="\<for\>[?!]\@!" start="\%(\%(^\|\.\.\.\=\|[{:,;([<>~\*/%&^|+-]\|\%(\<[_[:lower:]][_[:alnum:]]*\)\@<![!=?]\)\s*\)\@<=\<\%(until\|while\)\>" matchgroup=rubyRepeat end="\<end\>" contains=ALLBUT,@rubyNotTop nextgroup=rubyOptionalDoLine
-  endif
+  SynFold 'for' syn region rubyRepeatExpression start="\<for\>" start="\%(\%(^\|\.\.\.\=\|[{:,;([<>~\*/%&^|+=-]\|\%(\<\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*\)\@<![!?]\)\s*\)\@<=\<\%(until\|while\)\>" matchgroup=rubyRepeat skip="\<end:" end="\<end\>" contains=ALLBUT,@rubyNotTop nextgroup=rubyOptionalDoLine
 
   if !exists("ruby_minlines")
     let ruby_minlines = 500
   endif
-  exec "syn sync minlines=" . ruby_minlines
+  exe "syn sync minlines=" . ruby_minlines
 
 else
-  syn match rubyControl "\<def\>[?!]\@!"    nextgroup=rubyMethodDeclaration skipwhite skipnl
-  syn match rubyControl "\<class\>[?!]\@!"  nextgroup=rubyClassDeclaration  skipwhite skipnl
-  syn match rubyControl "\<module\>[?!]\@!" nextgroup=rubyModuleDeclaration skipwhite skipnl
-  syn match rubyControl "\<\%(case\|begin\|do\|for\|if\|unless\|while\|until\|else\|elsif\|ensure\|then\|when\|end\)\>[?!]\@!"
-  syn match rubyKeyword "\<\%(alias\|undef\)\>[?!]\@!"
+  syn match rubyControl "\<def\>"    nextgroup=rubyMethodDeclaration skipwhite skipnl
+  syn match rubyControl "\<class\>"  nextgroup=rubyClassDeclaration  skipwhite skipnl
+  syn match rubyControl "\<module\>" nextgroup=rubyModuleDeclaration skipwhite skipnl
+  syn match rubyControl "\<\%(case\|begin\|do\|for\|if\|unless\|while\|until\|else\|elsif\|rescue\|ensure\|then\|when\|end\)\>"
+  syn match rubyKeyword "\<\%(alias\|undef\)\>"
 endif
 
 " Special Methods {{{1
 if !exists("ruby_no_special_methods")
-  syn keyword rubyAccess    public protected private public_class_method private_class_method public_constant private_constant module_function
-  " attr is a common variable name
-  syn match   rubyAttribute "\%(\%(^\|;\)\s*\)\@<=attr\>\(\s*[.=]\)\@!"
-  syn keyword rubyAttribute attr_accessor attr_reader attr_writer
-  syn match   rubyControl   "\<\%(exit!\|\%(abort\|at_exit\|exit\|fork\|loop\|trap\)\>[?!]\@!\)"
-  syn keyword rubyEval	    eval class_eval instance_eval module_eval
-  syn keyword rubyException raise fail catch throw
-  syn keyword rubyInclude   autoload gem load require require_relative
-  syn keyword rubyKeyword   callcc caller lambda proc
-  " false positive with 'include?'
-  syn match   rubyMacro     "\<include\>[?!]\@!"
-  syn keyword rubyMacro     extend prepend refine using
-  syn keyword rubyMacro     alias_method define_method define_singleton_method remove_method undef_method
+  syn match rubyAccess	  "\<\%(public\|protected\|private\)\>" " use re=2
+  syn match rubyAccess	  "\%#=1\<\%(public\|private\)_class_method\>"
+  syn match rubyAccess	  "\%#=1\<\%(public\|private\)_constant\>"
+  syn match rubyAccess	  "\%#=1\<module_function\>"
+  syn match rubyAttribute "\%#=1\%(\%(^\|;\)\s*\)\@<=attr\>\(\s*[.=]\)\@!" " attr is a common variable name
+  syn match rubyAttribute "\%#=1\<attr_\%(accessor\|reader\|writer\)\>"
+  syn match rubyControl   "\%#=1\<\%(abort\|at_exit\|exit\|fork\|loop\|trap\)\>"
+  syn match rubyEval	  "\%#=1\<eval\>"
+  syn match rubyEval	  "\%#=1\<\%(class\|instance\|module\)_eval\>"
+  syn match rubyException "\%#=1\<\%(raise\|fail\|catch\|throw\)\>"
+  syn match rubyInclude   "\%#=1\<\%(autoload\|gem\|load\|require\%(_relative\)\=\)\>"
+  syn match rubyKeyword   "\%#=1\<\%(callcc\|caller\|lambda\|proc\)\>"
+  syn match rubyMacro	  "\%#=1\<\%(extend\|include\|prepend\|refine\|using\)\>"
+  syn match rubyMacro	  "\%#=1\<\%(alias\|define\|define_singleton\|remove\|undef\)_method\>"
 endif
 
 " Comments and Documentation {{{1
-syn match   rubySharpBang "\%^#!.*" display
-syn keyword rubyTodo	  FIXME NOTE TODO OPTIMIZE HACK REVIEW XXX todo contained
-syn match   rubyComment   "#.*" contains=rubySharpBang,rubySpaceError,rubyTodo,@Spell
+syn match   rubySharpBang    "\%^#!.*" display
+syn keyword rubyTodo	     FIXME NOTE TODO OPTIMIZE HACK REVIEW XXX todo contained
+syn match   rubyEncoding     "[[:alnum:]-]\+" contained display
+syn match   rubyMagicComment "\c\%<3l#\s*\zs\%(coding\|encoding\):"					contained nextgroup=rubyEncoding skipwhite
+syn match   rubyMagicComment "\c\%<10l#\s*\zs\%(frozen_string_literal\|warn_indent\|warn_past_scope\):" contained nextgroup=rubyBoolean  skipwhite
+syn match   rubyComment	     "#.*" contains=@rubyCommentSpecial,rubySpaceError,@Spell
+
+syn cluster rubyCommentSpecial contains=rubySharpBang,rubyTodo,rubyMagicComment
+syn cluster rubyCommentNotTop  contains=@rubyCommentSpecial,rubyEncoding
+
 if !exists("ruby_no_comment_fold") && s:foldable('#')
   syn region rubyMultilineComment start="^\s*#.*\n\%(^\s*#\)\@=" end="^\s*#.*\n\%(^\s*#\)\@!" contains=rubyComment transparent fold keepend
-  syn region rubyDocumentation	  start="^=begin\ze\%(\s.*\)\=$" end="^=end\%(\s.*\)\=$" contains=rubySpaceError,rubyTodo,@Spell fold
+  syn region rubyDocumentation	  start="^=begin\ze\%(\s.*\)\=$" end="^=end\%(\s.*\)\=$"      contains=rubySpaceError,rubyTodo,@Spell fold
 else
-  syn region rubyDocumentation	  start="^=begin\s*$" end="^=end\s*$" contains=rubySpaceError,rubyTodo,@Spell
+  syn region rubyDocumentation	  start="^=begin\s*$"		 end="^=end\s*$"              contains=rubySpaceError,rubyTodo,@Spell
 endif
 
+" {{{1 Useless Line Continuations
+syn match rubyUselessLineContinuation "\%([.:,;{([<>~\*%&^|+=-]\|%(\%(\w\|[^\x00-\x7F]\)\@1<![?!]\)\s*\zs\\$" nextgroup=rubyUselessLineContinuation skipwhite skipempty
+syn match rubyUselessLineContinuation "\\$"								      nextgroup=rubyUselessLineContinuation skipwhite skipempty contained
+
 " Keyword Nobbling {{{1
-" Note: this is a hack to prevent 'keywords' being highlighted as such when called as methods with an explicit receiver
-syn match rubyKeywordAsMethod "\%(\%(\.\@1<!\.\)\|::\)\_s*\%([_[:lower:]][_[:alnum:]]*\|\<\%(BEGIN\|END\)\>\)" transparent contains=NONE
-syn match rubyKeywordAsMethod "\(defined?\|exit!\)\@!\<[_[:lower:]][_[:alnum:]]*[?!]"			       transparent contains=NONE
+" prevent methods with keyword names being highlighted as keywords when called
+syn match rubyKeywordAsMethod "\%(\%(\.\@1<!\.\)\|&\.\|::\)\_s*\%([_[:lower:]][_[:alnum:]]*\|\%(BEGIN\|END\)\>\)" transparent contains=rubyDotOperator,rubyScopeOperator
 
-" More Symbols {{{1
-syn match  rubySymbol		"\%([{(,]\_s*\)\zs\l\w*[!?]\=::\@!"he=e-1
-syn match  rubySymbol		"[]})\"':]\@1<!\<\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*[!?]\=:[[:space:],]\@="he=e-1
-syn match  rubySymbol		"\%([{(,]\_s*\)\zs[[:space:],{]\l\w*[!?]\=::\@!"hs=s+1,he=e-1
-syn match  rubySymbol		"[[:space:],{(]\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*[!?]\=:[[:space:],]\@="hs=s+1,he=e-1
+" Bang and Predicate Methods and Operators {{{1
+syn match rubyBangPredicateMethod "\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*[?!]"
+
+if !exists("ruby_no_special_methods")
+  syn match rubyControl "\%#=1\<exit!" display
+endif
+syn match rubyDefinedOperator "\%#=1\<defined?" display
+
+" 1.9-style Hash Keys and Keyword Parameters {{{1
+syn match rubySymbol "\%([{(|,]\_s*\)\@<=\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*[?!]\=::\@!"he=e-1
+syn match rubySymbol "[]})\"':]\@1<!\<\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*[!?]\=:[[:space:],;]\@="he=e-1
+syn match rubySymbol "[[:space:],{(]\%(\h\|[^\x00-\x7F]\)\%(\w\|[^\x00-\x7F]\)*[!?]\=:[[:space:],;]\@="hs=s+1,he=e-1
 
 " __END__ Directive {{{1
-if s:foldable('__END__')
-  syn region rubyData matchgroup=rubyDataDirective start="^__END__$" end="\%$" fold
-else
-  syn region rubyData matchgroup=rubyDataDirective start="^__END__$" end="\%$"
-endif
+SynFold '__END__' syn region rubyData matchgroup=rubyDataDirective start="^__END__$" end="\%$"
 
 " Default Highlighting {{{1
 hi def link rubyClass			rubyDefine
 hi def link rubyModule			rubyDefine
-hi def link rubyMethodExceptional	rubyDefine
+hi def link rubyExceptionHandler2	rubyDefine
 hi def link rubyDefine			Define
 hi def link rubyAccess			rubyMacro
 hi def link rubyAttribute		rubyMacro
@@ -488,14 +481,15 @@
 hi def link rubyFunction		Function
 hi def link rubyConditional		Conditional
 hi def link rubyConditionalModifier	rubyConditional
-hi def link rubyExceptional		rubyConditional
+hi def link rubyExceptionHandler	rubyConditional
+hi def link rubyRescueModifier		rubyExceptionHandler
 hi def link rubyRepeat			Repeat
 hi def link rubyRepeatModifier		rubyRepeat
 hi def link rubyOptionalDo		rubyRepeat
 hi def link rubyControl			Statement
 hi def link rubyInclude			Include
 hi def link rubyInteger			Number
-hi def link rubyASCIICode		Character
+hi def link rubyCharacter		Character
 hi def link rubyFloat			Float
 hi def link rubyBoolean			Boolean
 hi def link rubyException		Exception
@@ -515,39 +509,80 @@
 hi def link rubyPredefinedVariable	rubyPredefinedIdentifier
 hi def link rubySymbol			Constant
 hi def link rubyKeyword			Keyword
+
 hi def link rubyOperator		Operator
+hi def link rubyDefinedOperator		rubyOperator
+hi def link rubyEnglishBooleanOperator	rubyOperator
+if exists("ruby_operators")
+  hi def link rubyTernaryOperator	rubyOperator
+  hi def link rubyArithmeticOperator	rubyOperator
+  hi def link rubyComparisonOperator	rubyOperator
+  hi def link rubyBitwiseOperator	rubyOperator
+  hi def link rubyBooleanOperator	rubyOperator
+  hi def link rubyRangeOperator		rubyOperator
+  hi def link rubyAssignmentOperator	rubyOperator
+  hi def link rubyEqualityOperator	rubyOperator
+endif
+
+if exists("ruby_pseudo_operators")
+  hi def link rubyPseudoOperator	Special
+  hi def link rubyDotOperator		rubyPseudoOperator
+  hi def link rubyScopeOperator		rubyPseudoOperator
+  hi def link rubySuperClassOperator	rubyPseudoOperator
+  hi def link rubyEigenClassOperator	rubyPseudoOperator
+  hi def link rubyLambdaOperator	rubyPseudoOperator
+  hi def link rubyDoubleSplatOperator	rubyPseudoOperator
+  hi def link rubySplatOperator		rubyPseudoOperator
+  hi def link rubyProcOperator		rubyPseudoOperator
+endif
+
 hi def link rubyBeginEnd		Statement
 hi def link rubyEval			Statement
 hi def link rubyPseudoVariable		Constant
-hi def link rubyCapitalizedMethod	rubyLocalVariableOrMethod
+hi def link rubyCapitalizedMethod	NONE
 
 hi def link rubyComment			Comment
+hi def link rubyEncoding		Constant
+hi def link rubyMagicComment		SpecialComment
 hi def link rubyData			Comment
 hi def link rubyDataDirective		Delimiter
 hi def link rubyDocumentation		Comment
 hi def link rubyTodo			Todo
 
+hi def link rubyBackslashEscape		rubyStringEscape
 hi def link rubyQuoteEscape		rubyStringEscape
+hi def link rubySpaceEscape		rubyStringEscape
+hi def link rubyParenthesisEscape	rubyStringEscape
+hi def link rubyCurlyBraceEscape	rubyStringEscape
+hi def link rubyAngleBracketEscape	rubyStringEscape
+hi def link rubySquareBracketEscape	rubyStringEscape
 hi def link rubyStringEscape		Special
+
 hi def link rubyInterpolationDelimiter	Delimiter
-hi def link rubyNoInterpolation		rubyString
 hi def link rubySharpBang		PreProc
+hi def link rubyStringDelimiter		Delimiter
+hi def link rubyHeredocDelimiter	rubyStringDelimiter
+hi def link rubyPercentRegexpDelimiter	rubyRegexpDelimiter
+hi def link rubyPercentStringDelimiter	rubyStringDelimiter
+hi def link rubyPercentSymbolDelimiter	rubySymbolDelimiter
 hi def link rubyRegexpDelimiter		rubyStringDelimiter
 hi def link rubySymbolDelimiter		rubySymbol
-hi def link rubyStringDelimiter		Delimiter
-hi def link rubyHeredoc			rubyString
 hi def link rubyString			String
 hi def link rubyRegexpEscape		rubyRegexpSpecial
 hi def link rubyRegexpQuantifier	rubyRegexpSpecial
 hi def link rubyRegexpAnchor		rubyRegexpSpecial
 hi def link rubyRegexpDot		rubyRegexpCharClass
 hi def link rubyRegexpCharClass		rubyRegexpSpecial
+hi def link rubyRegexpIntersection	rubyRegexpSpecial
 hi def link rubyRegexpSpecial		Special
 hi def link rubyRegexpComment		Comment
 hi def link rubyRegexp			rubyString
 
-hi def link rubyInvalidVariable		Error
 hi def link rubyError			Error
+if exists("ruby_line_continuation_error")
+  hi def link rubyUselessLineContinuation rubyError
+endif
+hi def link rubyGlobalVariableError	rubyError
 hi def link rubySpaceError		rubyError
 
 " Postscript {{{1
@@ -556,4 +591,6 @@
 let &cpo = s:cpo_sav
 unlet! s:cpo_sav
 
+delc SynFold
+
 " vim: nowrap sw=2 sts=2 ts=8 noet fdm=marker: