vim-patch:8c1b8cb2e0b5 (#18966)

Update runtime files
https://github.com/vim/vim/commit/8c1b8cb2e0b52d0853f85c2096a2f22dbc57a788

9 files changed, 378 insertions, 262 deletions

diff --git a/runtime/syntax/mason.vim b/runtime/syntax/mason.vim
index f087def794..e1638ece75 100644
--- a/runtime/syntax/mason.vim
+++ b/runtime/syntax/mason.vim
@@ -1,11 +1,12 @@
 " Vim syntax file
-" Language:     Mason (Perl embedded in HTML)
-" Maintainer:   vim-perl <vim-perl@googlegroups.com>
-" Homepage:      http://github.com/vim-perl/vim-perl/tree/master
-" Bugs/requests: http://github.com/vim-perl/vim-perl/issues
-" Last Change:  2017-09-12
-" Contributors: Hinrik Örn Sigurðsson <hinrik.sig@gmail.com>
-"               Andrew Smith <andrewdsmith@yahoo.com>
+" Language:      Mason (Perl embedded in HTML)
+" Maintainer:    vim-perl <vim-perl@googlegroups.com>
+" Homepage:      https://github.com/vim-perl/vim-perl
+" Bugs/requests: https://github.com/vim-perl/vim-perl/issues
+" License:       Vim License (see :help license)
+" Last Change:   2021 Oct 10
+" Contributors:  Hinrik Örn Sigurðsson <hinrik.sig@gmail.com>
+"                Andrew Smith <andrewdsmith@yahoo.com>
 "
 " TODO:
 "  - Fix <%text> blocks to show HTML tags but ignore Mason tags.
@@ -74,6 +75,7 @@ syn cluster masonTop contains=masonLine,masonExpr,masonPerl,masonComp,masonArgs,
 " syntax files.
 hi def link masonDoc Comment
 hi def link masonPod Comment
+hi def link podOrdinary masonPod
 hi def link masonPerlComment perlComment
 
 let b:current_syntax = "mason"
diff --git a/runtime/syntax/perl.vim b/runtime/syntax/perl.vim
index f4f9520de5..59611b66a4 100644
--- a/runtime/syntax/perl.vim
+++ b/runtime/syntax/perl.vim
@@ -1,15 +1,17 @@
 " Vim syntax file
-" Language:      Perl 5
+" Language:      Perl
 " Maintainer:    vim-perl <vim-perl@googlegroups.com>
-" Homepage:      https://github.com/vim-perl/vim-perl/tree/master
+" Homepage:      https://github.com/vim-perl/vim-perl
 " Bugs/requests: https://github.com/vim-perl/vim-perl/issues
-" Last Change:   2020 Apr 15
+" License:       Vim License (see :help license)
+" Last Change:   2021 Oct 7
 " Contributors:  Andy Lester <andy@petdance.com>
 "                Hinrik Örn Sigurðsson <hinrik.sig@gmail.com>
 "                Lukas Mai <l.mai.web.de>
 "                Nick Hibma <nick@van-laarhoven.org>
 "                Sonia Heimann <niania@netsurf.org>
 "                Rob Hoelz <rob@hoelz.ro>
+"                Doug Kearns <dougkearns@gmail.com>
 "                and many others.
 "
 " Please download the most recent version first, before mailing
@@ -41,11 +43,11 @@ set cpo&vim
 
 " POD starts with ^=<word> and ends with ^=cut
 
-if !exists("perl_include_pod") || perl_include_pod == 1
+if get(g:, 'perl_include_pod', 1)
   " Include a while extra syntax file
   syn include @Pod syntax/pod.vim
   unlet b:current_syntax
-  if exists("perl_fold")
+  if get(g:, 'perl_fold', 1)
     syn region perlPOD start="^=[a-z]" end="^=cut" contains=@Pod,@Spell,perlTodo keepend fold extend
     syn region perlPOD start="^=cut" end="^=cut" contains=perlTodo keepend fold extend
   else
@@ -54,7 +56,7 @@ if !exists("perl_include_pod") || perl_include_pod == 1
   endif
 else
   " Use only the bare minimum of rules
-  if exists("perl_fold")
+  if get(g:, 'perl_fold', 1)
     syn region perlPOD start="^=[a-z]" end="^=cut" fold
   else
     syn region perlPOD start="^=[a-z]" end="^=cut"
@@ -92,7 +94,7 @@ syn match perlStatementFiles		"\<\%(ch\%(dir\|mod\|own\|root\)\|glob\|link\|mkdi
 syn match perlStatementFiles		"-[rwxoRWXOezsfdlpSbctugkTBMAC]\>"
 syn match perlStatementFlow		"\<\%(caller\|die\|dump\|eval\|exit\|wantarray\|evalbytes\)\>"
 syn match perlStatementInclude		"\<\%(require\|import\|unimport\)\>"
-syn match perlStatementInclude		"\<\%(use\|no\)\s\+\%(\%(attributes\|attrs\|autodie\|autouse\|parent\|base\|big\%(int\|num\|rat\)\|blib\|bytes\|charnames\|constant\|diagnostics\|encoding\%(::warnings\)\=\|feature\|fields\|filetest\|if\|integer\|less\|lib\|locale\|mro\|open\|ops\|overload\|overloading\|re\|sigtrap\|sort\|strict\|subs\|threads\%(::shared\)\=\|utf8\|vars\|version\|vmsish\|warnings\%(::register\)\=\)\>\)\="
+syn match perlStatementInclude		"\<\%(use\|no\)\s\+\%(\%(attributes\|attrs\|autodie\%(::\%(exception\%(::system\)\=\|hints\|skip\)\)\=\|autouse\|parent\|base\|big\%(int\|num\|rat\)\|blib\|bytes\|charnames\|constant\|deprecate\|diagnostics\|encoding\%(::warnings\)\=\|experimental\|feature\|fields\|filetest\|if\|integer\|less\|lib\|locale\|mro\|ok\|open\|ops\|overload\|overloading\|re\|sigtrap\|sort\|strict\|subs\|threads\%(::shared\)\=\|utf8\|vars\|version\|vmsish\|warnings\%(::register\)\=\)\>\)\="
 syn match perlStatementProc		"\<\%(alarm\|exec\|fork\|get\%(pgrp\|ppid\|priority\)\|kill\|pipe\|set\%(pgrp\|priority\)\|sleep\|system\|times\|wait\%(pid\)\=\)\>"
 syn match perlStatementSocket		"\<\%(accept\|bind\|connect\|get\%(peername\|sock\%(name\|opt\)\)\|listen\|recv\|send\|setsockopt\|shutdown\|socket\%(pair\)\=\)\>"
 syn match perlStatementIPC		"\<\%(msg\%(ctl\|get\|rcv\|snd\)\|sem\%(ctl\|get\|op\)\|shm\%(ctl\|get\|read\|write\)\)\>"
@@ -138,38 +140,36 @@ syn match  perlPackageRef	 "[$@#%*&]\%(\%(::\|'\)\=\I\i*\%(\%(::\|'\)\I\i*\)*\)\
 " If you don't want complex things like @{${"foo"}} to be processed,
 " just set the variable "perl_no_extended_vars"...
 
-if !exists("perl_no_scope_in_variables")
-  syn match  perlVarPlain       "\%([@$]\|\$#\)\$*\%(\I\i*\)\=\%(\%(::\|'\)\I\i*\)*\%(::\|\i\@<=\)" contains=perlPackageRef nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref
-  syn match  perlVarPlain2                   "%\$*\%(\I\i*\)\=\%(\%(::\|'\)\I\i*\)*\%(::\|\i\@<=\)" contains=perlPackageRef nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref
-  syn match  perlFunctionName                "&\$*\%(\I\i*\)\=\%(\%(::\|'\)\I\i*\)*\%(::\|\i\@<=\)" contains=perlPackageRef nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref
+if !get(g:, 'perl_no_scope_in_variables', 0)
+  syn match  perlVarPlain       "\%([@$]\|\$#\)\$*\%(\I\i*\)\=\%(\%(::\|'\)\I\i*\)*\%(::\|\i\@<=\)" contains=perlPackageRef nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref
+  syn match  perlVarPlain2                   "%\$*\%(\I\i*\)\=\%(\%(::\|'\)\I\i*\)*\%(::\|\i\@<=\)" contains=perlPackageRef nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref
+  syn match  perlFunctionName                "&\$*\%(\I\i*\)\=\%(\%(::\|'\)\I\i*\)*\%(::\|\i\@<=\)" contains=perlPackageRef nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref
 else
-  syn match  perlVarPlain       "\%([@$]\|\$#\)\$*\%(\I\i*\)\=\%(\%(::\|'\)\I\i*\)*\%(::\|\i\@<=\)" nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref
-  syn match  perlVarPlain2                   "%\$*\%(\I\i*\)\=\%(\%(::\|'\)\I\i*\)*\%(::\|\i\@<=\)" nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref
-  syn match  perlFunctionName                "&\$*\%(\I\i*\)\=\%(\%(::\|'\)\I\i*\)*\%(::\|\i\@<=\)" nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref
+  syn match  perlVarPlain       "\%([@$]\|\$#\)\$*\%(\I\i*\)\=\%(\%(::\|'\)\I\i*\)*\%(::\|\i\@<=\)" nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref
+  syn match  perlVarPlain2                   "%\$*\%(\I\i*\)\=\%(\%(::\|'\)\I\i*\)*\%(::\|\i\@<=\)" nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref
+  syn match  perlFunctionName                "&\$*\%(\I\i*\)\=\%(\%(::\|'\)\I\i*\)*\%(::\|\i\@<=\)" nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref
 endif
 
 syn match  perlVarPlain2	 "%[-+]"
 
-if !exists("perl_no_extended_vars")
-  syn cluster perlExpr		contains=perlStatementIndirObjWrap,perlStatementScalar,perlStatementRegexp,perlStatementNumeric,perlStatementList,perlStatementHash,perlStatementFiles,perlStatementTime,perlStatementMisc,perlVarPlain,perlVarPlain2,perlVarNotInMatches,perlVarSlash,perlVarBlock,perlVarBlock2,perlShellCommand,perlFloat,perlNumber,perlStringUnexpanded,perlString,perlQQ,perlArrow,perlBraces
-  syn region perlArrow		matchgroup=perlArrow start="->\s*(" end=")" contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref contained
-  syn region perlArrow		matchgroup=perlArrow start="->\s*\[" end="\]" contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref contained
-  syn region perlArrow		matchgroup=perlArrow start="->\s*{" end="}" contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref contained
-  syn match  perlArrow		"->\s*{\s*\I\i*\s*}" contains=perlVarSimpleMemberName nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref contained
-  syn region perlArrow		matchgroup=perlArrow start="->\s*\$*\I\i*\s*(" end=")" contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref contained
-  syn region perlVarBlock	matchgroup=perlVarPlain start="\%($#\|[$@]\)\$*{" skip="\\}" end=+}\|\%(\%(<<\%('\|"\)\?\)\@=\)+ contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref extend
-  syn region perlVarBlock2	matchgroup=perlVarPlain start="[%&*]\$*{" skip="\\}" end=+}\|\%(\%(<<\%('\|"\)\?\)\@=\)+ contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref extend
-  syn match  perlVarPlain2	"[%&*]\$*{\I\i*}" nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref extend
-  syn match  perlVarPlain	"\%(\$#\|[@$]\)\$*{\I\i*}" nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref extend
-  syn region perlVarMember	matchgroup=perlVarPlain start="\%(->\)\={" skip="\\}" end="}" contained contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref extend
-  syn match  perlVarSimpleMember	"\%(->\)\={\s*\I\i*\s*}" nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref contains=perlVarSimpleMemberName contained extend
+if !get(g:, 'perl_no_extended_vars', 0)
+  syn cluster perlExpr		contains=perlStatementIndirObjWrap,perlStatementScalar,perlStatementRegexp,perlStatementNumeric,perlStatementList,perlStatementHash,perlStatementFiles,perlStatementTime,perlStatementMisc,perlVarPlain,perlVarPlain2,perlVarNotInMatches,perlVarSlash,perlVarBlock,perlVarBlock2,perlShellCommand,perlFloat,perlNumber,perlStringUnexpanded,perlString,perlQ,perlQQ,perlQW,perlQR,perlArrow,perlBraces
+  syn region perlArrow		matchgroup=perlArrow start="->\s*(" end=")" contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref contained
+  syn region perlArrow		matchgroup=perlArrow start="->\s*\[" end="\]" contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref contained
+  syn region perlArrow		matchgroup=perlArrow start="->\s*{" end="}" contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref contained
+  syn match  perlArrow		"->\s*{\s*\I\i*\s*}" contains=perlVarSimpleMemberName nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref contained
+  syn region perlVarBlock	matchgroup=perlVarPlain start="\%($#\|[$@]\)\$*{" skip="\\}" end=+}\|\%(\%(<<\%('\|"\)\?\)\@=\)+ contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref extend
+  syn region perlVarBlock2	matchgroup=perlVarPlain start="[%&*]\$*{" skip="\\}" end=+}\|\%(\%(<<\%('\|"\)\?\)\@=\)+ contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref extend
+  syn match  perlVarPlain2	"[%&*]\$*{\I\i*}" nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref extend
+  syn match  perlVarPlain	"\%(\$#\|[@$]\)\$*{\I\i*}" nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref extend
+  syn region perlVarMember	matchgroup=perlVarPlain start="\%(->\)\={" skip="\\}" end="}" contained contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref extend
+  syn match  perlVarSimpleMember	"\%(->\)\={\s*\I\i*\s*}" nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref contains=perlVarSimpleMemberName contained extend
   syn match  perlVarSimpleMemberName	"\I\i*" contained
-  syn region perlVarMember	matchgroup=perlVarPlain start="\%(->\)\=\[" skip="\\]" end="]" contained contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlMethod,perlPostDeref extend
-  syn match perlPackageConst	"__PACKAGE__" nextgroup=perlMethod,perlPostDeref
-  syn match  perlMethod		"->\$*\I\i*" contained nextgroup=perlVarSimpleMember,perlVarMember,perlMethod,perlPostDeref
-  syn match  perlPostDeref	"->\%($#\|[$@%&*]\)\*" contained nextgroup=perlVarSimpleMember,perlVarMember,perlMethod,perlPostDeref
-  syn region  perlPostDeref	start="->\%($#\|[$@%&*]\)\[" skip="\\]" end="]" contained contains=@perlExpr nextgroup=perlVarSimpleMember,perlVarMember,perlMethod,perlPostDeref
-  syn region  perlPostDeref	matchgroup=perlPostDeref start="->\%($#\|[$@%&*]\){" skip="\\}" end="}" contained contains=@perlExpr nextgroup=perlVarSimpleMember,perlVarMember,perlMethod,perlPostDeref
+  syn region perlVarMember	matchgroup=perlVarPlain start="\%(->\)\=\[" skip="\\]" end="]" contained contains=@perlExpr nextgroup=perlVarMember,perlVarSimpleMember,perlPostDeref extend
+  syn match perlPackageConst	"__PACKAGE__" nextgroup=perlPostDeref
+  syn match  perlPostDeref	"->\%($#\|[$@%&*]\)\*" contained nextgroup=perlVarSimpleMember,perlVarMember,perlPostDeref
+  syn region  perlPostDeref	start="->\%($#\|[$@%&*]\)\[" skip="\\]" end="]" contained contains=@perlExpr nextgroup=perlVarSimpleMember,perlVarMember,perlPostDeref
+  syn region  perlPostDeref	matchgroup=perlPostDeref start="->\%($#\|[$@%&*]\){" skip="\\}" end="}" keepend extend contained contains=@perlExpr nextgroup=perlVarSimpleMember,perlVarMember,perlPostDeref
 endif
 
 " File Descriptors
@@ -221,10 +221,16 @@ syn region  perlShellCommand	matchgroup=perlMatchStartEnd start="`" end="`" cont
 " Constants
 "
 " Numbers
-syn match  perlNumber	"\<\%(0\%(x\x[[:xdigit:]_]*\|b[01][01_]*\|\o[0-7_]*\|\)\|[1-9][[:digit:]_]*\)\>"
-syn match  perlFloat	"\<\d[[:digit:]_]*[eE][\-+]\=\d\+"
-syn match  perlFloat	"\<\d[[:digit:]_]*\.[[:digit:]_]*\%([eE][\-+]\=\d\+\)\="
-syn match  perlFloat    "\.[[:digit:]][[:digit:]_]*\%([eE][\-+]\=\d\+\)\="
+syn case   ignore
+syn match  perlNumber	"\<\%(0\|[1-9]\%(_\=\d\)*\)\>"
+syn match  perlNumber	"\<0\%(x\x\%(_\=\x\)*\|b[01]\%(_\=[01]\)*\|o\=\%(_\=\o\)*\)\>"
+syn match  perlFloat	"\<\d\%(_\=\d\)*e[-+]\=\d\%(_\=\d\)*"
+syn match  perlFloat	"\<\d\%(_\=\d\)*\.\%(\d\%(_\=\d\)*\)\=\%(e[-+]\=\d\%(_\=\d\)*\)\="
+syn match  perlFloat    "\.\d\%(_\=\d\)*\%(e[-+]\=\d\%(_\=\d\)*\)\="
+syn match  perlFloat	"\<0x\x\%(_\=\x\)*p[-+]\=\d\%(_\=\d\)*"
+syn match  perlFloat	"\<0x\x\%(_\=\x\)*\.\%(\x\%(_\=\x\)*\)\=\%(p[-+]\=\d\%(_\=\d\)*\)\="
+syn match  perlFloat    "\<0x\.\x\%(_\=\x\)*\%(p[-+]\=\d\%(_\=\d\)*\)\="
+syn case   match
 
 syn match  perlString	"\<\%(v\d\+\%(\.\d\+\)*\|\d\+\%(\.\d\+\)\{2,}\)\>" contains=perlVStringV
 syn match  perlVStringV	"\<v" contained
@@ -242,22 +248,24 @@ syn region perlAnglesDQ		start=+<+ end=+>+ extend contained contains=perlAnglesD
 
 
 " Simple version of searches and matches
-syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\>\s*\z([^[:space:]'([{<#]\)+ end=+\z1[msixpodualgcn]*+ contains=@perlInterpMatch keepend extend
-syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m#+ end=+#[msixpodualgcn]*+ contains=@perlInterpMatch keepend extend
-syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\s*'+ end=+'[msixpodualgcn]*+ contains=@perlInterpSQ keepend extend
-syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\s*/+ end=+/[msixpodualgcn]*+ contains=@perlInterpSlash keepend extend
-syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\s*(+ end=+)[msixpodualgcn]*+ contains=@perlInterpMatch,perlParensDQ keepend extend
-syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\s*{+ end=+}[msixpodualgcn]*+ contains=@perlInterpMatch,perlBracesDQ extend
-syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\s*<+ end=+>[msixpodualgcn]*+ contains=@perlInterpMatch,perlAnglesDQ keepend extend
-syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\s*\[+ end=+\][msixpodualgcn]*+ contains=@perlInterpMatch,perlBracketsDQ keepend extend
+syn match  perlMatchModifiers "[msixpadluncgo]\+" contained
+syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\>\s*\z([^[:space:]'([{<#]\)+ end=+\z1+ contains=@perlInterpMatch keepend extend nextgroup=perlMatchModifiers
+syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m#+ end=+#+ contains=@perlInterpMatch keepend extend nextgroup=perlMatchModifiers
+syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\s*'+ end=+'+ contains=@perlInterpSQ keepend extend nextgroup=perlMatchModifiers
+syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\s*/+ end=+/+ contains=@perlInterpSlash keepend extend nextgroup=perlMatchModifiers
+syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\s*(+ end=+)+ contains=@perlInterpMatch,perlParensDQ keepend extend nextgroup=perlMatchModifiers
+syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\s*{+ end=+}+ contains=@perlInterpMatch,perlBracesDQ extend nextgroup=perlMatchModifiers
+syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\s*<+ end=+>+ contains=@perlInterpMatch,perlAnglesDQ keepend extend nextgroup=perlMatchModifiers
+syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!m\s*\[+ end=+\]+ contains=@perlInterpMatch,perlBracketsDQ keepend extend nextgroup=perlMatchModifiers
 
 " Below some hacks to recognise the // variant. This is virtually impossible to catch in all
 " cases as the / is used in so many other ways, but these should be the most obvious ones.
-syn region perlMatch	matchgroup=perlMatchStartEnd start="\%([$@%&*]\@<!\%(\<split\|\<while\|\<if\|\<unless\|\.\.\|[-+*!~(\[{=]\)\s*\)\@<=/\%(/=\)\@!" start=+^/\%(/=\)\@!+ start=+\s\@<=/\%(/=\)\@![^[:space:][:digit:]$@%=]\@=\%(/\_s*\%([([{$@%&*[:digit:]"'`]\|\_s\w\|[[:upper:]_abd-fhjklnqrt-wyz]\)\)\@!+ skip=+\\/+ end=+/[msixpodualgcn]*+ contains=@perlInterpSlash extend
+syn region perlMatch	matchgroup=perlMatchStartEnd start="\%([$@%&*]\@<!\%(\<split\|\<while\|\<if\|\<unless\|\.\.\|[-+*!~(\[{=]\)\s*\)\@<=/\%(/=\)\@!" start=+^/\%(/=\)\@!+ start=+\s\@<=/\%(/=\)\@![^[:space:][:digit:]$@%=]\@=\%(/\_s*\%([([{$@%&*[:digit:]"'`]\|\_s\w\|[[:upper:]_abd-fhjklnqrt-wyz]\)\)\@!+ skip=+\\/+ end=+/+ contains=@perlInterpSlash extend nextgroup=perlMatchModifiers
 
 
 " Substitutions
 " perlMatch is the first part, perlSubstitution* is the substitution part
+syn match  perlSubstitutionModifiers "[msixpadluncgero]\+" contained
 syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!s\>\s*\z([^[:space:]'([{<#]\)+ end=+\z1+me=e-1 contains=@perlInterpMatch nextgroup=perlSubstitutionGQQ keepend extend
 syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!s\s*'+  end=+'+me=e-1 contains=@perlInterpSQ nextgroup=perlSubstitutionSQ keepend extend
 syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!s\s*/+  end=+/+me=e-1 contains=@perlInterpSlash nextgroup=perlSubstitutionGQQ keepend extend
@@ -266,38 +274,39 @@ syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!s\s
 syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!s\s*<+ end=+>+ contains=@perlInterpMatch,perlAnglesDQ nextgroup=perlSubstitutionGQQ skipwhite skipempty skipnl keepend extend
 syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!s\s*\[+ end=+\]+ contains=@perlInterpMatch,perlBracketsDQ nextgroup=perlSubstitutionGQQ skipwhite skipempty skipnl keepend extend
 syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!s\s*{+ end=+}+ contains=@perlInterpMatch,perlBracesDQ nextgroup=perlSubstitutionGQQ skipwhite skipempty skipnl keepend extend
-syn region perlSubstitutionGQQ		matchgroup=perlMatchStartEnd start=+\z([^[:space:]'([{<]\)+ end=+\z1[msixpodualgcern]*+ keepend contained contains=@perlInterpDQ extend
-syn region perlSubstitutionGQQ		matchgroup=perlMatchStartEnd start=+(+ end=+)[msixpodualgcern]*+ contained contains=@perlInterpDQ,perlParensDQ keepend extend
-syn region perlSubstitutionGQQ		matchgroup=perlMatchStartEnd start=+\[+ end=+\][msixpodualgcern]*+ contained contains=@perlInterpDQ,perlBracketsDQ keepend extend
-syn region perlSubstitutionGQQ		matchgroup=perlMatchStartEnd start=+{+ end=+}[msixpodualgcern]*+ contained contains=@perlInterpDQ,perlBracesDQ keepend extend extend
-syn region perlSubstitutionGQQ		matchgroup=perlMatchStartEnd start=+<+ end=+>[msixpodualgcern]*+ contained contains=@perlInterpDQ,perlAnglesDQ keepend extend
-syn region perlSubstitutionSQ		matchgroup=perlMatchStartEnd start=+'+  end=+'[msixpodualgcern]*+ contained contains=@perlInterpSQ keepend extend
+syn region perlSubstitutionGQQ		matchgroup=perlMatchStartEnd start=+\z([^[:space:]'([{<]\)+ end=+\z1+ keepend contained contains=@perlInterpDQ extend nextgroup=perlSubstitutionModifiers
+syn region perlSubstitutionGQQ		matchgroup=perlMatchStartEnd start=+(+ end=+)+ contained contains=@perlInterpDQ,perlParensDQ keepend extend nextgroup=perlSubstitutionModifiers
+syn region perlSubstitutionGQQ		matchgroup=perlMatchStartEnd start=+\[+ end=+\]+ contained contains=@perlInterpDQ,perlBracketsDQ keepend extend nextgroup=perlSubstitutionModifiers
+syn region perlSubstitutionGQQ		matchgroup=perlMatchStartEnd start=+{+ end=+}+ contained contains=@perlInterpDQ,perlBracesDQ keepend extend extend nextgroup=perlSubstitutionModifiers
+syn region perlSubstitutionGQQ		matchgroup=perlMatchStartEnd start=+<+ end=+>+ contained contains=@perlInterpDQ,perlAnglesDQ keepend extend nextgroup=perlSubstitutionModifiers
+syn region perlSubstitutionSQ		matchgroup=perlMatchStartEnd start=+'+  end=+'+ contained contains=@perlInterpSQ keepend extend nextgroup=perlSubstitutionModifiers
 
 " Translations
 " perlMatch is the first part, perlTranslation* is the second, translator part.
+syn match  perlTranslationModifiers "[cdsr]\+" contained
 syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!\%(tr\|y\)\>\s*\z([^[:space:]([{<#]\)+ end=+\z1+me=e-1 contains=@perlInterpSQ nextgroup=perlTranslationGQ
 syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!\%(tr\|y\)#+ end=+#+me=e-1 contains=@perlInterpSQ nextgroup=perlTranslationGQ
 syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!\%(tr\|y\)\s*\[+ end=+\]+ contains=@perlInterpSQ,perlBracketsSQ nextgroup=perlTranslationGQ skipwhite skipempty skipnl
 syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!\%(tr\|y\)\s*(+ end=+)+ contains=@perlInterpSQ,perlParensSQ nextgroup=perlTranslationGQ skipwhite skipempty skipnl
 syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!\%(tr\|y\)\s*<+ end=+>+ contains=@perlInterpSQ,perlAnglesSQ nextgroup=perlTranslationGQ skipwhite skipempty skipnl
 syn region perlMatch	matchgroup=perlMatchStartEnd start=+\<\%(::\|'\|->\)\@<!\%(tr\|y\)\s*{+ end=+}+ contains=@perlInterpSQ,perlBracesSQ nextgroup=perlTranslationGQ skipwhite skipempty skipnl
-syn region perlTranslationGQ		matchgroup=perlMatchStartEnd start=+\z([^[:space:]([{<]\)+ end=+\z1[cdsr]*+ contained
-syn region perlTranslationGQ		matchgroup=perlMatchStartEnd start=+(+ end=+)[cdsr]*+ contains=perlParensSQ contained
-syn region perlTranslationGQ		matchgroup=perlMatchStartEnd start=+\[+ end=+\][cdsr]*+ contains=perlBracketsSQ contained
-syn region perlTranslationGQ		matchgroup=perlMatchStartEnd start=+{+ end=+}[cdsr]*+ contains=perlBracesSQ contained
-syn region perlTranslationGQ		matchgroup=perlMatchStartEnd start=+<+ end=+>[cdsr]*+ contains=perlAnglesSQ contained
+syn region perlTranslationGQ		matchgroup=perlMatchStartEnd start=+\z([^[:space:]([{<]\)+ end=+\z1+ contained nextgroup=perlTranslationModifiers
+syn region perlTranslationGQ		matchgroup=perlMatchStartEnd start=+(+ end=+)+ contains=perlParensSQ contained nextgroup=perlTranslationModifiers
+syn region perlTranslationGQ		matchgroup=perlMatchStartEnd start=+\[+ end=+\]+ contains=perlBracketsSQ contained nextgroup=perlTranslationModifiers
+syn region perlTranslationGQ		matchgroup=perlMatchStartEnd start=+{+ end=+}+ contains=perlBracesSQ contained nextgroup=perlTranslationModifiers
+syn region perlTranslationGQ		matchgroup=perlMatchStartEnd start=+<+ end=+>+ contains=perlAnglesSQ contained nextgroup=perlTranslationModifiers
 
 
 " Strings and q, qq, qw and qr expressions
 
 syn region perlStringUnexpanded	matchgroup=perlStringStartEnd start="'" end="'" contains=@perlInterpSQ keepend extend
 syn region perlString		matchgroup=perlStringStartEnd start=+"+  end=+"+ contains=@perlInterpDQ keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q\>\s*\z([^[:space:]#([{<]\)+ end=+\z1+ contains=@perlInterpSQ keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q#+ end=+#+ contains=@perlInterpSQ keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q\s*(+ end=+)+ contains=@perlInterpSQ,perlParensSQ keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q\s*\[+ end=+\]+ contains=@perlInterpSQ,perlBracketsSQ keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q\s*{+ end=+}+ contains=@perlInterpSQ,perlBracesSQ keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q\s*<+ end=+>+ contains=@perlInterpSQ,perlAnglesSQ keepend extend
+syn region perlQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q\>\s*\z([^[:space:]#([{<]\)+ end=+\z1+ contains=@perlInterpSQ keepend extend
+syn region perlQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q#+ end=+#+ contains=@perlInterpSQ keepend extend
+syn region perlQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q\s*(+ end=+)+ contains=@perlInterpSQ,perlParensSQ keepend extend
+syn region perlQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q\s*\[+ end=+\]+ contains=@perlInterpSQ,perlBracketsSQ keepend extend
+syn region perlQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q\s*{+ end=+}+ contains=@perlInterpSQ,perlBracesSQ keepend extend
+syn region perlQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q\s*<+ end=+>+ contains=@perlInterpSQ,perlAnglesSQ keepend extend
 
 syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q[qx]\>\s*\z([^[:space:]#([{<]\)+ end=+\z1+ contains=@perlInterpDQ keepend extend
 syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q[qx]#+ end=+#+ contains=@perlInterpDQ keepend extend
@@ -306,48 +315,83 @@ syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q[qx
 syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q[qx]\s*{+ end=+}+ contains=@perlInterpDQ,perlBracesDQ keepend extend
 syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!q[qx]\s*<+ end=+>+ contains=@perlInterpDQ,perlAnglesDQ keepend extend
 
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qw\s*\z([^[:space:]#([{<]\)+  end=+\z1+ contains=@perlInterpSQ keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qw#+  end=+#+ contains=@perlInterpSQ keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qw\s*(+  end=+)+ contains=@perlInterpSQ,perlParensSQ keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qw\s*\[+  end=+\]+ contains=@perlInterpSQ,perlBracketsSQ keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qw\s*{+  end=+}+ contains=@perlInterpSQ,perlBracesSQ keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qw\s*<+  end=+>+ contains=@perlInterpSQ,perlAnglesSQ keepend extend
+syn region perlQW		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qw\s*\z([^[:space:]#([{<]\)+  end=+\z1+ contains=@perlInterpSQ keepend extend
+syn region perlQW		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qw#+  end=+#+ contains=@perlInterpSQ keepend extend
+syn region perlQW		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qw\s*(+  end=+)+ contains=@perlInterpSQ,perlParensSQ keepend extend
+syn region perlQW		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qw\s*\[+  end=+\]+ contains=@perlInterpSQ,perlBracketsSQ keepend extend
+syn region perlQW		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qw\s*{+  end=+}+ contains=@perlInterpSQ,perlBracesSQ keepend extend
+syn region perlQW		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qw\s*<+  end=+>+ contains=@perlInterpSQ,perlAnglesSQ keepend extend
 
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\>\s*\z([^[:space:]#([{<'/]\)+  end=+\z1[imosxdual]*+ contains=@perlInterpMatch keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\s*/+  end=+/[imosxdual]*+ contains=@perlInterpSlash keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr#+  end=+#[imosxdual]*+ contains=@perlInterpMatch keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\s*'+  end=+'[imosxdual]*+ contains=@perlInterpSQ keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\s*(+  end=+)[imosxdual]*+ contains=@perlInterpMatch,perlParensDQ keepend extend
+syn match  perlQRModifiers "[msixpadluno]\+" contained
+syn region perlQR		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\>\s*\z([^[:space:]#([{<'/]\)+  end=+\z1+ contains=@perlInterpMatch keepend extend nextgroup=perlQRModifiers
+syn region perlQR		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\s*/+  end=+/+ contains=@perlInterpSlash keepend extend nextgroup=perlQRModifiers
+syn region perlQR		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr#+  end=+#+ contains=@perlInterpMatch keepend extend nextgroup=perlQRModifiers
+syn region perlQR		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\s*'+  end=+'+ contains=@perlInterpSQ keepend extend nextgroup=perlQRModifiers
+syn region perlQR		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\s*(+  end=+)+ contains=@perlInterpMatch,perlParensDQ keepend extend nextgroup=perlQRModifiers
 
 " A special case for qr{}, qr<> and qr[] which allows for comments and extra whitespace in the pattern
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\s*{+  end=+}[imosxdual]*+ contains=@perlInterpMatch,perlBracesDQ,perlComment keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\s*<+  end=+>[imosxdual]*+ contains=@perlInterpMatch,perlAnglesDQ,perlComment keepend extend
-syn region perlQQ		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\s*\[+  end=+\][imosxdual]*+ contains=@perlInterpMatch,perlBracketsDQ,perlComment keepend extend
+syn region perlQR		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\s*{+  end=+}+ contains=@perlInterpMatch,perlBracesDQ,perlComment keepend extend nextgroup=perlQRModifiers
+syn region perlQR		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\s*<+  end=+>+ contains=@perlInterpMatch,perlAnglesDQ,perlComment keepend extend nextgroup=perlQRModifiers
+syn region perlQR		matchgroup=perlStringStartEnd start=+\<\%(::\|'\|->\)\@<!qr\s*\[+  end=+\]+ contains=@perlInterpMatch,perlBracketsDQ,perlComment keepend extend nextgroup=perlQRModifiers
 
 " Constructs such as print <<EOF [...] EOF, 'here' documents
 "
 " XXX Any statements after the identifier are in perlString colour (i.e.
 " 'if $a' in 'print <<EOF if $a'). This is almost impossible to get right it
 " seems due to the 'auto-extending nature' of regions.
-syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\z(\I\i*\)+  end=+$+     contains=@perlTop oneline
-syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\s*"\z([^\\"]*\%(\\.[^\\"]*\)*\)"+ end=+$+ contains=@perlTop oneline
-syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\s*'\z([^\\']*\%(\\.[^\\']*\)*\)'+ end=+$+ contains=@perlTop oneline
-syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\s*""+       end=+$+     contains=@perlTop oneline
-syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\s*''+       end=+$+     contains=@perlTop oneline
-if exists("perl_fold")
-  syn region perlHereDoc	start=+<<\z(\I\i*\)+ matchgroup=perlStringStartEnd      end=+^\z1$+ contains=perlHereDocStart,@perlInterpDQ fold extend
+" XXX Indented heredocs are not perfect - they sometimes seem to take a moment
+"     to update if switched from double to single quotes and vice versa.
+"
+" Note: bare delimiters such as << to mean <<"" are not supported. These are a
+"       fatal error since 5.28 and, apparently, a rarely used feature.
+
+syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\~\=\I\i*+                         end=+$+     contains=@perlTop oneline
+syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\~\=\\\I\i*+                       end=+$+     contains=@perlTop oneline
+syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\~\=\s*"[^\\"]*\%(\\.[^\\"]*\)*"+  end=+$+     contains=@perlTop oneline
+syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\~\=\s*'[^\\']*\%(\\.[^\\']*\)*'+  end=+$+     contains=@perlTop oneline
+syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\~\=\s*`[^\\`]*\%(\\.[^\\`]*\)*`+  end=+$+     contains=@perlTop oneline
+syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\~\=\s*""+                         end=+$+     contains=@perlTop oneline
+syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\~\=\s*''+                         end=+$+     contains=@perlTop oneline
+syn region perlHereDocStart	matchgroup=perlStringStartEnd start=+<<\~\=\s*``+                         end=+$+     contains=@perlTop oneline
+
+if get(g:, 'perl_fold', 0)
+  syn region perlHereDoc	start=+<<\z(\I\i*\)+                        matchgroup=perlStringStartEnd end=+^\z1$+ contains=perlHereDocStart,@perlInterpDQ fold extend
+  syn region perlHereDoc	start=+<<\\\z(\I\i*\)+                      matchgroup=perlStringStartEnd end=+^\z1$+ contains=perlHereDocStart,@perlInterpSQ fold extend
   syn region perlHereDoc	start=+<<\s*"\z([^\\"]*\%(\\.[^\\"]*\)*\)"+ matchgroup=perlStringStartEnd end=+^\z1$+ contains=perlHereDocStart,@perlInterpDQ fold extend
   syn region perlHereDoc	start=+<<\s*'\z([^\\']*\%(\\.[^\\']*\)*\)'+ matchgroup=perlStringStartEnd end=+^\z1$+ contains=perlHereDocStart,@perlInterpSQ fold extend
-  syn region perlHereDoc	start=+<<\s*""+ matchgroup=perlStringStartEnd           end=+^$+    contains=perlHereDocStart,@perlInterpDQ,perlNotEmptyLine fold extend
-  syn region perlHereDoc	start=+<<\s*''+ matchgroup=perlStringStartEnd           end=+^$+    contains=perlHereDocStart,@perlInterpSQ,perlNotEmptyLine fold extend
-  syn region perlAutoload	matchgroup=perlStringStartEnd start=+<<\s*\(['"]\=\)\z(END_\%(SUB\|OF_FUNC\|OF_AUTOLOAD\)\)\1+ end=+^\z1$+ contains=ALL fold extend
+  syn region perlHereDoc	start=+<<\s*`\z([^\\`]*\%(\\.[^\\`]*\)*\)`+ matchgroup=perlStringStartEnd end=+^\z1$+ contains=perlHereDocStart,@perlInterpDQ fold extend
+  syn region perlHereDoc	start=+<<\s*""+                             matchgroup=perlStringStartEnd end=+^$+    contains=perlHereDocStart,@perlInterpDQ,perlNotEmptyLine fold extend
+  syn region perlHereDoc	start=+<<\s*''+                             matchgroup=perlStringStartEnd end=+^$+    contains=perlHereDocStart,@perlInterpSQ,perlNotEmptyLine fold extend
+  syn region perlHereDoc	start=+<<\s*``+                             matchgroup=perlStringStartEnd end=+^$+    contains=perlHereDocStart,@perlInterpDQ,perlNotEmptyLine fold extend
 else
-  syn region perlHereDoc	start=+<<\z(\I\i*\)+ matchgroup=perlStringStartEnd      end=+^\z1$+ contains=perlHereDocStart,@perlInterpDQ
+  syn region perlHereDoc	start=+<<\z(\I\i*\)+                        matchgroup=perlStringStartEnd end=+^\z1$+ contains=perlHereDocStart,@perlInterpDQ
+  syn region perlHereDoc	start=+<<\\\z(\I\i*\)+                      matchgroup=perlStringStartEnd end=+^\z1$+ contains=perlHereDocStart,@perlInterpSQ
   syn region perlHereDoc	start=+<<\s*"\z([^\\"]*\%(\\.[^\\"]*\)*\)"+ matchgroup=perlStringStartEnd end=+^\z1$+ contains=perlHereDocStart,@perlInterpDQ
   syn region perlHereDoc	start=+<<\s*'\z([^\\']*\%(\\.[^\\']*\)*\)'+ matchgroup=perlStringStartEnd end=+^\z1$+ contains=perlHereDocStart,@perlInterpSQ
-  syn region perlHereDoc	start=+<<\s*""+ matchgroup=perlStringStartEnd           end=+^$+    contains=perlHereDocStart,@perlInterpDQ,perlNotEmptyLine
-  syn region perlHereDoc	start=+<<\s*''+ matchgroup=perlStringStartEnd           end=+^$+    contains=perlHereDocStart,@perlInterpSQ,perlNotEmptyLine
-  syn region perlAutoload	matchgroup=perlStringStartEnd start=+<<\s*\(['"]\=\)\z(END_\%(SUB\|OF_FUNC\|OF_AUTOLOAD\)\)\1+ end=+^\z1$+ contains=ALL
+  syn region perlHereDoc	start=+<<\s*`\z([^\\`]*\%(\\.[^\\`]*\)*\)`+ matchgroup=perlStringStartEnd end=+^\z1$+ contains=perlHereDocStart,@perlInterpDQ
+  syn region perlHereDoc	start=+<<\s*""+                             matchgroup=perlStringStartEnd end=+^$+    contains=perlHereDocStart,@perlInterpDQ,perlNotEmptyLine
+  syn region perlHereDoc	start=+<<\s*''+                             matchgroup=perlStringStartEnd end=+^$+    contains=perlHereDocStart,@perlInterpSQ,perlNotEmptyLine
+  syn region perlHereDoc	start=+<<\s*``+                             matchgroup=perlStringStartEnd end=+^$+    contains=perlHereDocStart,@perlInterpDQ,perlNotEmptyLine
+endif
+
+if get(g:, 'perl_fold', 0)
+  syn region perlIndentedHereDoc	start=+<<\~\z(\I\i*\)+                        matchgroup=perlStringStartEnd end=+^\s*\z1$+ contains=perlIndentedHereDocStart,@perlInterpDQ fold extend
+  syn region perlIndentedHereDoc	start=+<<\~\\\z(\I\i*\)+                      matchgroup=perlStringStartEnd end=+^\s*\z1$+ contains=perlIndentedHereDocStart,@perlInterpSQ fold extend
+  syn region perlIndentedHereDoc	start=+<<\~\s*"\z([^\\"]*\%(\\.[^\\"]*\)*\)"+ matchgroup=perlStringStartEnd end=+^\s*\z1$+ contains=perlIndentedHereDocStart,@perlInterpDQ fold extend
+  syn region perlIndentedHereDoc	start=+<<\~\s*'\z([^\\']*\%(\\.[^\\']*\)*\)'+ matchgroup=perlStringStartEnd end=+^\s*\z1$+ contains=perlIndentedHereDocStart,@perlInterpSQ fold extend
+  syn region perlIndentedHereDoc	start=+<<\~\s*`\z([^\\`]*\%(\\.[^\\`]*\)*\)`+ matchgroup=perlStringStartEnd end=+^\s*\z1$+ contains=perlIndentedHereDocStart,@perlInterpDQ fold extend
+  syn region perlIndentedHereDoc	start=+<<\~\s*""+                             matchgroup=perlStringStartEnd end=+^$+       contains=perlIndentedHereDocStart,@perlInterpDQ,perlNotEmptyLine fold extend
+  syn region perlIndentedHereDoc	start=+<<\~\s*''+                             matchgroup=perlStringStartEnd end=+^$+       contains=perlIndentedHereDocStart,@perlInterpSQ,perlNotEmptyLine fold extend
+  syn region perlIndentedHereDoc	start=+<<\~\s*``+                             matchgroup=perlStringStartEnd end=+^$+       contains=perlIndentedHereDocStart,@perlInterpDQ,perlNotEmptyLine fold extend
+else
+  syn region perlIndentedHereDoc	start=+<<\~\z(\I\i*\)+                        matchgroup=perlStringStartEnd end=+^\s*\z1$+ contains=perlHereDocStart,@perlInterpDQ
+  syn region perlIndentedHereDoc	start=+<<\~\\\z(\I\i*\)+                      matchgroup=perlStringStartEnd end=+^\s*\z1$+ contains=perlHereDocStart,@perlInterpSQ
+  syn region perlIndentedHereDoc	start=+<<\~\s*"\z([^\\"]*\%(\\.[^\\"]*\)*\)"+ matchgroup=perlStringStartEnd end=+^\s*\z1$+ contains=perlHereDocStart,@perlInterpDQ
+  syn region perlIndentedHereDoc	start=+<<\~\s*'\z([^\\']*\%(\\.[^\\']*\)*\)'+ matchgroup=perlStringStartEnd end=+^\s*\z1$+ contains=perlHereDocStart,@perlInterpSQ
+  syn region perlIndentedHereDoc	start=+<<\~\s*`\z([^\\`]*\%(\\.[^\\`]*\)*\)`+ matchgroup=perlStringStartEnd end=+^\s*\z1$+ contains=perlHereDocStart,@perlInterpDQ
+  syn region perlIndentedHereDoc	start=+<<\~\s*""+                             matchgroup=perlStringStartEnd end=+^$+       contains=perlHereDocStart,@perlInterpDQ,perlNotEmptyLine
+  syn region perlIndentedHereDoc	start=+<<\~\s*''+                             matchgroup=perlStringStartEnd end=+^$+       contains=perlHereDocStart,@perlInterpSQ,perlNotEmptyLine
+  syn region perlIndentedHereDoc	start=+<<\~\s*``+                             matchgroup=perlStringStartEnd end=+^$+       contains=perlHereDocStart,@perlInterpDQ,perlNotEmptyLine
 endif
 
 
@@ -357,24 +401,15 @@ syn match   perlPackageDecl		"\<package\s\+\%(\h\|::\)\%(\w\|::\)*" contains=per
 syn keyword perlStatementPackage	package contained
 
 " Functions
-"       sub [name] [(prototype)] {
-"
-syn match perlSubError "[^[:space:];{#]" contained
-syn match perlSubAttributesCont "\h\w*\_s*\%(:\_s*\)\=" nextgroup=@perlSubAttrMaybe contained
-syn region perlSubAttributesCont matchgroup=perlSubAttributesCont start="\h\w*(" end=")\_s*\%(:\_s*\)\=" nextgroup=@perlSubAttrMaybe contained contains=@perlInterpSQ,perlParensSQ
-syn cluster perlSubAttrMaybe contains=perlSubAttributesCont,perlSubError,perlFakeGroup
-syn match perlSubAttributes "" contained nextgroup=perlSubError
-syn match perlSubAttributes ":\_s*" contained nextgroup=@perlSubAttrMaybe
 if get(g:, "perl_sub_signatures", 0)
-    syn match perlSignature +(\_[^)]*)\_s*+ nextgroup=perlSubAttributes,perlComment contained
+    syn match perlSubSignature "\s*([^)]*)" contained extend
 else
-    syn match perlSubPrototypeError "(\%(\_s*\%(\%(\\\%([$@%&*]\|\[[$@%&*]\+\]\)\|[$&*]\|[@%]\%(\_s*)\)\@=\|;\%(\_s*[)$@%&*\\]\)\@=\|_\%(\_s*[);]\)\@=\)\_s*\)*\)\@>\zs\_[^)]\+" contained
-    syn match perlSubPrototype +(\_[^)]*)\_s*+ nextgroup=perlSubAttributes,perlComment contained contains=perlSubPrototypeError
+    syn match perlSubPrototype "\s*([\\$@%&*\[\];]*)" contained extend
 endif
-
-syn match perlSubName +\%(\h\|::\|'\w\)\%(\w\|::\|'\w\)*\_s*\|+ contained nextgroup=perlSubPrototype,perlSignature,perlSubAttributes,perlComment
-
-syn match perlFunction +\<sub\>\_s*+ nextgroup=perlSubName
+syn match perlSubAttribute "\s*:\s*\h\w*\%(([^)]*)\|\)" contained extend
+syn match perlSubName "\%(\h\|::\|'\w\)\%(\w\|::\|'\w\)*\s*" contained extend
+syn region perlSubDeclaration start="" end="[;{]" contains=perlSubName,perlSubPrototype,perlSubAttribute,perlSubSignature,perlComment contained transparent
+syn match perlFunction "\<sub\>\_s*" nextgroup=perlSubDeclaration
 
 " The => operator forces a bareword to the left of it to be interpreted as
 " a string
@@ -394,39 +429,68 @@ syn match  perlFormatField	"@[^A-Za-z_|<>~#*]"me=e-1 contained
 syn match  perlFormatField	"@$" contained
 
 " __END__ and __DATA__ clauses
-if exists("perl_fold")
-  syntax region perlDATA		start="^__DATA__$" skip="." end="." contains=@perlDATA fold
-  syntax region perlDATA		start="^__END__$" skip="." end="." contains=perlPOD,@perlDATA fold
+
+" Vim excludes empty syn-region end lines from the fold region.  This is
+" probably a bug and means a DATA section ending with an empty line does not
+" have that final line included in the fold.
+"
+" As a workaround we exploit an unterminated syntax region here with an end
+" pattern that will (probably) never match.  This forces all lines to be
+" included in the fold region.  Of course, if it does match then there's
+" nothing to work around as it is a non-empty line.
+"
+" This problem also exists with empty string delimited heredocs but there's no
+" known workaround for that case.
+if get(g:, 'perl_fold', 0)
+  syntax region perlDATA matchgroup=perlDATAStart start="^__DATA__$" end="VIM_PERL_EOF\%$" contains=perlPOD,@perlDATA fold
+  syntax region perlEND  matchgroup=perlENDStart  start="^__END__$"  end="VIM_PERL_EOF\%$" contains=perlPOD,@perlDATA fold
 else
-  syntax region perlDATA		start="^__DATA__$" skip="." end="." contains=@perlDATA
-  syntax region perlDATA		start="^__END__$" skip="." end="." contains=perlPOD,@perlDATA
+  syntax region perlDATA matchgroup=perlDATAStart start="^__DATA__$" end="\%$" contains=perlPOD,@perlDATA
+  syntax region perlEND  matchgroup=perlENDStart  start="^__END__$"  end="\%$" contains=perlPOD,@perlDATA
 endif
 
 "
 " Folding
-
-if exists("perl_fold")
+if get(g:, 'perl_fold', 0)
   " Note: this bit must come before the actual highlighting of the "package"
   " keyword, otherwise this will screw up Pod lines that match /^package/
-  if !exists("perl_nofold_packages")
+  if !get(g:, 'perl_nofold_packages', 0)
     syn region perlPackageFold start="^package \S\+;\s*\%(#.*\)\=$" end="^1;\=\s*\%(#.*\)\=$" end="\n\+package"me=s-1 transparent fold keepend
+    syn region perlPackageFold start="^\z(\s*\)package\s*\S\+\s*{" end="^\z1}" transparent fold keepend
   endif
-  if !exists("perl_nofold_subs")
+  if !get(g:, 'perl_nofold_subs', 0)
     if get(g:, "perl_fold_anonymous_subs", 0)
-      syn region perlSubFold start="\<sub\>[^{]*{" end="}" transparent fold keepend extend
-      syn region perlSubFold start="\<\%(BEGIN\|END\|CHECK\|INIT\)\>\s*{" end="}" transparent fold keepend
+      " EXPLANATION:
+      " \<sub\>                  - "sub" keyword
+      " \_[^;{]*                 - any characters, including new line, but not ";" or "{", zero or more times
+      " \%(([\\$@%&*\[\];]*)\)\= - prototype definition, \$@%&*[]; characters between (), zero or 1 times
+      " \_[^;]*                  - any characters, including new line, but not ";" or "{", zero or more times
+      " {                        - start subroutine block
+      syn region perlSubFold start="\<sub\>\_[^;{]*\%(([\\$@%&*\[\];]*)\)\=\_[^;{]*{" end="}" transparent fold keepend extend
     else
-      syn region perlSubFold     start="^\z(\s*\)\<sub\>.*[^};]$" end="^\z1}\s*\%(#.*\)\=$" transparent fold keepend
-      syn region perlSubFold start="^\z(\s*\)\<\%(BEGIN\|END\|CHECK\|INIT\|UNITCHECK\)\>.*[^};]$" end="^\z1}\s*$" transparent fold keepend
+      " EXPLANATION:
+      " same, as above, but first non-space character after "sub" keyword must
+      " be [A-Za-z_] 
+      syn region perlSubFold start="\<sub\>\s*\h\_[^;{]*\%(([\\$@%&*\[\];]*)\)\=\_[^;]*{" end="}" transparent fold keepend extend
     endif
+
+    syn region perlSubFold start="\<\%(BEGIN\|END\|CHECK\|INIT\|UNITCHECK\)\>\_s*{" end="}" transparent fold keepend
   endif
 
-  if exists("perl_fold_blocks")
+  if get(g:, 'perl_fold_blocks', 0)
     syn region perlBlockFold start="^\z(\s*\)\%(if\|elsif\|unless\|for\|while\|until\|given\)\s*(.*)\%(\s*{\)\=\s*\%(#.*\)\=$" start="^\z(\s*\)for\%(each\)\=\s*\%(\%(my\|our\)\=\s*\S\+\s*\)\=(.*)\%(\s*{\)\=\s*\%(#.*\)\=$" end="^\z1}\s*;\=\%(#.*\)\=$" transparent fold keepend
+
+    " TODO this is works incorrectly
     syn region perlBlockFold start="^\z(\s*\)\%(do\|else\)\%(\s*{\)\=\s*\%(#.*\)\=$" end="^\z1}\s*while" end="^\z1}\s*;\=\%(#.*\)\=$" transparent fold keepend
+  else
+    if get(g:, 'perl_fold_do_blocks', 0)
+      syn region perlDoBlockDeclaration start="" end="{" contains=perlComment contained transparent
+      syn match perlOperator "\<do\>\_s*" nextgroup=perlDoBlockDeclaration
+
+      syn region perlDoBlockFold start="\<do\>\_[^{]*{" end="}" transparent fold keepend extend
+    endif
   endif
 
-  setlocal foldmethod=syntax
   syn sync fromstart
 else
   " fromstart above seems to set minlines even if perl_fold is not set.
@@ -438,29 +502,28 @@ endif
 
 " The default highlighting.
 hi def link perlSharpBang		PreProc
-hi def link perlControl		PreProc
-hi def link perlInclude		Include
-hi def link perlSpecial		Special
-hi def link perlString		String
+hi def link perlControl			PreProc
+hi def link perlInclude			Include
+hi def link perlSpecial			Special
+hi def link perlString			String
 hi def link perlCharacter		Character
-hi def link perlNumber		Number
-hi def link perlFloat		Float
+hi def link perlNumber			Number
+hi def link perlFloat			Float
 hi def link perlType			Type
 hi def link perlIdentifier		Identifier
-hi def link perlLabel		Label
+hi def link perlLabel			Label
 hi def link perlStatement		Statement
 hi def link perlConditional		Conditional
-hi def link perlRepeat		Repeat
+hi def link perlRepeat			Repeat
 hi def link perlOperator		Operator
 hi def link perlFunction		Keyword
-hi def link perlSubName		Function
+hi def link perlSubName			Function
 hi def link perlSubPrototype		Type
-hi def link perlSignature		Type
-hi def link perlSubAttributes	PreProc
-hi def link perlSubAttributesCont	perlSubAttributes
-hi def link perlComment		Comment
+hi def link perlSubSignature		Type
+hi def link perlSubAttribute		PreProc
+hi def link perlComment			Comment
 hi def link perlTodo			Todo
-if exists("perl_string_as_statement")
+if get(g:, 'perl_string_as_statement', 0)
   hi def link perlStringStartEnd	perlStatement
 else
   hi def link perlStringStartEnd	perlString
@@ -470,21 +533,29 @@ hi def link perlList			perlStatement
 hi def link perlMisc			perlStatement
 hi def link perlVarPlain		perlIdentifier
 hi def link perlVarPlain2		perlIdentifier
-hi def link perlArrow		perlIdentifier
+hi def link perlArrow			perlIdentifier
 hi def link perlFiledescRead		perlIdentifier
 hi def link perlFiledescStatement	perlIdentifier
-hi def link perlVarSimpleMember	perlIdentifier
-hi def link perlVarSimpleMemberName 	perlString
-hi def link perlVarNotInMatches	perlIdentifier
+hi def link perlVarSimpleMember		perlIdentifier
+hi def link perlVarSimpleMemberName	perlString
+hi def link perlVarNotInMatches		perlIdentifier
 hi def link perlVarSlash		perlIdentifier
+hi def link perlQ			perlString
 hi def link perlQQ			perlString
-hi def link perlHereDoc		perlString
+hi def link perlQW			perlString
+hi def link perlQR			perlString
+hi def link perlMatchModifiers          perlMatchStartEnd
+hi def link perlSubstitutionModifiers   perlMatchStartEnd
+hi def link perlTranslationModifiers    perlMatchStartEnd
+hi def link perlQRModifiers             perlStringStartEnd
+hi def link perlHereDoc			perlString
+hi def link perlIndentedHereDoc		perlString
 hi def link perlStringUnexpanded	perlString
-hi def link perlSubstitutionSQ	perlString
-hi def link perlSubstitutionGQQ	perlString
-hi def link perlTranslationGQ	perlString
-hi def link perlMatch		perlString
-hi def link perlMatchStartEnd	perlStatement
+hi def link perlSubstitutionSQ		perlString
+hi def link perlSubstitutionGQQ		perlString
+hi def link perlTranslationGQ		perlString
+hi def link perlMatch			perlString
+hi def link perlMatchStartEnd		perlStatement
 hi def link perlFormatName		perlIdentifier
 hi def link perlFormatField		perlString
 hi def link perlPackageDecl		perlType
@@ -493,44 +564,48 @@ hi def link perlPackageRef		perlType
 hi def link perlStatementPackage	perlStatement
 hi def link perlStatementStorage	perlStatement
 hi def link perlStatementControl	perlStatement
-hi def link perlStatementScalar	perlStatement
-hi def link perlStatementRegexp	perlStatement
+hi def link perlStatementScalar		perlStatement
+hi def link perlStatementRegexp		perlStatement
 hi def link perlStatementNumeric	perlStatement
-hi def link perlStatementList	perlStatement
-hi def link perlStatementHash	perlStatement
-hi def link perlStatementIOfunc	perlStatement
+hi def link perlStatementList		perlStatement
+hi def link perlStatementHash		perlStatement
+hi def link perlStatementIOfunc		perlStatement
 hi def link perlStatementFiledesc	perlStatement
-hi def link perlStatementVector	perlStatement
-hi def link perlStatementFiles	perlStatement
-hi def link perlStatementFlow	perlStatement
+hi def link perlStatementVector		perlStatement
+hi def link perlStatementFiles		perlStatement
+hi def link perlStatementFlow		perlStatement
 hi def link perlStatementInclude	perlStatement
-hi def link perlStatementProc	perlStatement
-hi def link perlStatementSocket	perlStatement
+hi def link perlStatementProc		perlStatement
+hi def link perlStatementSocket		perlStatement
 hi def link perlStatementIPC		perlStatement
 hi def link perlStatementNetwork	perlStatement
-hi def link perlStatementPword	perlStatement
-hi def link perlStatementTime	perlStatement
-hi def link perlStatementMisc	perlStatement
+hi def link perlStatementPword		perlStatement
+hi def link perlStatementTime		perlStatement
+hi def link perlStatementMisc		perlStatement
 hi def link perlStatementIndirObj	perlStatement
 hi def link perlFunctionName		perlIdentifier
-hi def link perlMethod		perlIdentifier
+hi def link perlMethod			perlIdentifier
 hi def link perlPostDeref		perlIdentifier
 hi def link perlFunctionPRef		perlType
+
 if !get(g:, 'perl_include_pod', 1)
   hi def link perlPOD		perlComment
 endif
 hi def link perlShellCommand		perlString
 hi def link perlSpecialAscii		perlSpecial
-hi def link perlSpecialDollar	perlSpecial
-hi def link perlSpecialString	perlSpecial
-hi def link perlSpecialStringU	perlSpecial
+hi def link perlSpecialDollar		perlSpecial
+hi def link perlSpecialString		perlSpecial
+hi def link perlSpecialStringU		perlSpecial
 hi def link perlSpecialMatch		perlSpecial
+hi def link perlEND			perlComment
+hi def link perlENDStart		perlEND
 hi def link perlDATA			perlComment
+hi def link perlDATAStart		perlDATA
 
 " NOTE: Due to a bug in Vim (or more likely, a misunderstanding on my part),
-"       I had to remove the transparent property from the following regions
-"       in order to get them to highlight correctly.  Feel free to remove
-"       these and reinstate the transparent property if you know how.
+"	I had to remove the transparent property from the following regions
+"	in order to get them to highlight correctly.  Feel free to remove
+"	these and reinstate the transparent property if you know how.
 hi def link perlParensSQ		perlString
 hi def link perlBracketsSQ		perlString
 hi def link perlBracesSQ		perlString
@@ -546,23 +621,21 @@ hi def link perlSpecialStringU2	perlString
 " Possible errors
 hi def link perlNotEmptyLine		Error
 hi def link perlElseIfError		Error
-hi def link perlSubPrototypeError	Error
-hi def link perlSubError		Error
 
 " Syncing to speed up processing
 "
-if !exists("perl_no_sync_on_sub")
+if !get(g:, 'perl_no_sync_on_sub', 0)
   syn sync match perlSync	grouphere NONE "^\s*\<package\s"
   syn sync match perlSync	grouphere NONE "^\s*\<sub\>"
   syn sync match perlSync	grouphere NONE "^}"
 endif
 
-if !exists("perl_no_sync_on_global_var")
+if !get(g:, 'perl_no_sync_on_global_var', 0)
   syn sync match perlSync	grouphere NONE "^$\I[[:alnum:]_:]+\s*=\s*{"
   syn sync match perlSync	grouphere NONE "^[@%]\I[[:alnum:]_:]+\s*=\s*("
 endif
 
-if exists("perl_sync_dist")
+if get(g:, 'perl_sync_dist', 0)
   execute "syn sync maxlines=" . perl_sync_dist
 else
   syn sync maxlines=100
diff --git a/runtime/syntax/pod.vim b/runtime/syntax/pod.vim
index 604713260b..44439cb2cd 100644
--- a/runtime/syntax/pod.vim
+++ b/runtime/syntax/pod.vim
@@ -2,9 +2,10 @@
 " Language:      Perl POD format
 " Maintainer:    vim-perl <vim-perl@googlegroups.com>
 " Previously:    Scott Bigham <dsb@killerbunnies.org>
-" Homepage:      http://github.com/vim-perl/vim-perl
-" Bugs/requests: http://github.com/vim-perl/vim-perl/issues
-" Last Change:   2017-09-12
+" Homepage:      https://github.com/vim-perl/vim-perl
+" Bugs/requests: https://github.com/vim-perl/vim-perl/issues
+" License:       Vim License (see :help license)
+" Last Change:   2021 Oct 8
 
 " To add embedded POD documentation highlighting to your syntax file, add
 " the commands:
@@ -27,71 +28,117 @@ endif
 let s:cpo_save = &cpo
 set cpo&vim
 
-" POD commands
-syn match podCommand    "^=encoding"  nextgroup=podCmdText contains=@NoSpell
-syn match podCommand    "^=head[1234]"  nextgroup=podCmdText contains=@NoSpell
-syn match podCommand    "^=item"        nextgroup=podCmdText contains=@NoSpell
-syn match podCommand    "^=over"        nextgroup=podOverIndent skipwhite contains=@NoSpell
-syn match podCommand    "^=back"        contains=@NoSpell
-syn match podCommand    "^=cut"         contains=@NoSpell
-syn match podCommand    "^=pod"         contains=@NoSpell
-syn match podCommand    "^=for"         nextgroup=podForKeywd skipwhite contains=@NoSpell
-syn match podCommand    "^=begin"       nextgroup=podForKeywd skipwhite contains=@NoSpell
-syn match podCommand    "^=end"         nextgroup=podForKeywd skipwhite contains=@NoSpell
+" TODO: add supported encodings when we can utilize better performing Vim 8 features
+syn match podEncoding	"[0-9A-Za-z_-]\+" contained contains=@NoSpell
 
 " Text of a =head1, =head2 or =item command
-syn match podCmdText	".*$" contained contains=podFormat,@NoSpell
+syn region podCmdText	start="\S.*$" end="^\ze\s*$" end="^\ze=cut\>" contained contains=podFormat,@NoSpell
 
 " Indent amount of =over command
-syn match podOverIndent	"\d\+" contained contains=@NoSpell
+syn match podOverIndent	"\d*\.\=\d\+\>" contained contains=@NoSpell
 
 " Formatter identifier keyword for =for, =begin and =end commands
 syn match podForKeywd	"\S\+" contained contains=@NoSpell
 
 " An indented line, to be displayed verbatim
-syn match podVerbatimLine	"^\s.*$" contains=@NoSpell
+syn region podVerbatim	start="^\s\+\S.*$" end="^\ze\s*$" end="^\ze=cut\>" contains=@NoSpell
+
+syn region podOrdinary	start="^\S.*$" end="^\ze\s*$" end="^\ze=cut\>" contains=podFormat,podSpecial,@Spell
 
 " Inline textual items handled specially by POD
 syn match podSpecial	"\(\<\|&\)\I\i*\(::\I\i*\)*([^)]*)" contains=@NoSpell
 syn match podSpecial	"[$@%]\I\i*\(::\I\i*\)*\>" contains=@NoSpell
 
 " Special formatting sequences
-syn region podFormat	start="[IBSCLFX]<[^<]"me=e-1 end=">" oneline contains=podFormat,@NoSpell
-syn region podFormat	start="[IBSCLFX]<<\s" end="\s>>" oneline contains=podFormat,@NoSpell
+
+syn cluster podFormat contains=podFormat,podFormatError
+
+syn match  podFormatError "[ADGHJKM-RT-WY]<"
+
+syn region podFormat	matchgroup=podFormatDelimiter start="[IBSCLFX]<"              end=">"              contains=@podFormat,@NoSpell
+syn region podFormat	matchgroup=podFormatDelimiter start="[IBSCLFX]<<\%(\s\+\|$\)" end="\%(\s\+\|^\)>>" contains=@podFormat,@NoSpell
+
 syn match  podFormat	"Z<>"
-syn match  podFormat	"E<\(\d\+\|\I\i*\)>" contains=podEscape,podEscape2,@NoSpell
-syn match  podEscape	"\I\i*>"me=e-1 contained contains=@NoSpell
-syn match  podEscape2	"\d\+>"me=e-1 contained contains=@NoSpell
+
+syn region podFormat	matchgroup=podFormatDelimiter start="E<" end=">" oneline contains=podEscape,podEscape2,@NoSpell
+
+" HTML entities {{{1
+" Source: Pod/Escapes.pm
+syn keyword podEscape contained lt gt quot amp apos sol verbar lchevron rchevron nbsp iexcl cent pound curren yen brvbar sect uml copy ordf laquo not shy reg macr deg plusmn sup2 sup3 acute micro para middot cedil sup1 ordm raquo frac14 frac12 frac34 iquest Agrave Aacute Acirc Atilde Auml Aring AElig Ccedil Egrave Eacute Ecirc Euml Igrave Iacute Icirc Iuml ETH Ntilde Ograve Oacute Ocirc Otilde Ouml times Oslash Ugrave Uacute Ucirc Uuml Yacute THORN szlig agrave aacute acirc atilde auml aring aelig ccedil egrave eacute ecirc euml igrave iacute icirc iuml eth ntilde ograve oacute ocirc otilde ouml divide oslash ugrave uacute ucirc uuml yacute thorn yuml fnof Alpha Beta Gamma Delta Epsilon Zeta Eta Theta Iota Kappa Lambda Mu Nu Xi Omicron Pi Rho Sigma Tau Upsilon Phi Chi Psi Omega alpha beta gamma delta epsilon zeta eta theta iota kappa lambda mu nu xi omicron pi rho sigmaf sigma tau upsilon phi chi psi omega thetasym upsih piv bull hellip prime Prime oline frasl weierp image real trade alefsym larr uarr rarr darr harr crarr lArr uArr rArr dArr hArr forall part exist empty nabla isin notin ni prod sum minus lowast radic prop infin ang and or cap cup int there4 sim cong asymp ne equiv le ge sub sup nsub sube supe oplus otimes perp sdot lceil rceil lfloor rfloor lang rang loz spades clubs hearts diams OElig oelig Scaron scaron Yuml circ tilde ensp emsp thinsp zwnj zwj lrm rlm ndash mdash lsquo rsquo sbquo ldquo rdquo bdquo dagger Dagger permil lsaquo rsaquo
+" }}}
+
+syn match  podEscape2	"\d\+"     contained contains=@NoSpell
+syn match  podEscape2	"0\=x\x\+" contained contains=@NoSpell
+syn match  podEscape2	"0\o\+"    contained contains=@NoSpell
+
+
+" POD commands
+syn match podCommand    "^=encoding\>"   nextgroup=podEncoding skipwhite contains=@NoSpell
+syn match podCommand    "^=head[1234]\>" nextgroup=podCmdText skipwhite skipnl contains=@NoSpell
+syn match podCommand    "^=item\>"       nextgroup=podCmdText skipwhite skipnl contains=@NoSpell
+syn match podCommand    "^=over\>"       nextgroup=podOverIndent skipwhite contains=@NoSpell
+syn match podCommand    "^=back"         contains=@NoSpell
+syn match podCommand    "^=cut"          contains=@NoSpell
+syn match podCommand    "^=pod"          contains=@NoSpell
+syn match podCommand    "^=for"          nextgroup=podForKeywd skipwhite contains=@NoSpell
+syn match podCommand    "^=begin"        nextgroup=podForKeywd skipwhite contains=@NoSpell
+syn match podCommand    "^=end"          nextgroup=podForKeywd skipwhite contains=@NoSpell
+
+" Comments
+
+syn keyword podForKeywd comment contained nextgroup=podForComment skipwhite skipnl
+
+if exists("perl_pod_no_comment_fold")
+  syn region podBeginComment start="^=begin\s\+comment\s*$" end="^=end\s\+comment\ze\s*$" keepend extend contains=podCommand
+  syn region podForComment start="\S.*$" end="^\ze\s*$" end="^\ze=cut\>" contained contains=@Spell,podTodo
+else
+  syn region podBeginComment start="^=begin\s\+comment\s*$" end="^=end\s\+comment\ze\s*$" keepend extend contains=podCommand,podTodo fold
+  syn region podForComment start="\S.*$" end="^\ze\s*$" end="^\ze=cut\>" contained contains=@Spell,podTodo fold
+endif
+
+syn keyword podTodo contained TODO FIXME XXX
+
+" Plain Pod files
+syn region podNonPod			   start="\%^\%(=\w\+\>\)\@!" end="^\ze=\a\w*\>"
+syn region podNonPod matchgroup=podCommand start="^=cut\>"	      end="\%$"
+syn region podNonPod matchgroup=podCommand start="^=cut\>"	      end="^\ze=\a\w*\>"
 
 " Define the default highlighting.
 " Only when an item doesn't have highlighting yet
 
 hi def link podCommand		Statement
+hi def link podBeginComment	Comment
+hi def link podForComment	Comment
+hi def link podNonPod		Comment
+hi def link podTodo		Todo
 hi def link podCmdText		String
+hi def link podEncoding		Constant
 hi def link podOverIndent	Number
 hi def link podForKeywd		Identifier
+hi def link podVerbatim		PreProc
 hi def link podFormat		Identifier
-hi def link podVerbatimLine	PreProc
+hi def link podFormatDelimiter	podFormat
+hi def link podFormatError	Error
 hi def link podSpecial		Identifier
-hi def link podEscape		String
+hi def link podEscape		Constant
 hi def link podEscape2		Number
 
 if exists("perl_pod_spellcheck_headings")
   " Spell-check headings
   syn clear podCmdText
-  syn match podCmdText    ".*$" contained contains=podFormat
+  syn region podCmdText start="\S.*$" end="^\s*$" end="^\ze=cut\>" contained contains=podFormat
 endif
 
 if exists("perl_pod_formatting")
   " By default, escapes like C<> are not checked for spelling. Remove B<>
   " and I<> from the list of escapes.
   syn clear podFormat
-  syn region podFormat start="[CLF]<[^<]"me=e-1 end=">" oneline contains=podFormat,@NoSpell
-  syn region podFormat start="[CLF]<<\s" end="\s>>" oneline contains=podFormat,@NoSpell
+  syn region podFormat start="[CLF]<[^<]"me=e-1 end=">" contains=@podFormat,@NoSpell
+  syn region podFormat start="[CLF]<<\%(\s\+\|$\)" end="\%(\s\+\|^\)>>" contains=@podFormat,@NoSpell
 
   " Don't spell-check inside E<>, but ensure that the E< itself isn't
   " marked as a spelling mistake.
-  syn match podFormat   "E<\(\d\+\|\I\i*\)>" contains=podEscape,podEscape2,@NoSpell
+  syn region podFormat	start="E<" end=">" oneline contains=podEscape,podEscape2,@NoSpell
 
   " Z<> is a mock formatting code. Ensure Z<> on its own isn't marked as a
   " spelling mistake.
@@ -105,41 +152,41 @@ if exists("perl_pod_formatting")
   syn match podIndexOpen   "X<" contains=@NoSpell
 
   " Same as above but for the << >> syntax.
-  syn match podBoldAlternativeDelimOpen    "B<< " contains=@NoSpell
-  syn match podItalicAlternativeDelimOpen  "I<< " contains=@NoSpell
-  syn match podNoSpaceAlternativeDelimOpen "S<< " contains=@NoSpell
-  syn match podIndexAlternativeDelimOpen   "X<< " contains=@NoSpell
+  syn match podBoldAlternativeDelimOpen    "B<<\%(\s\+\|$\)" contains=@NoSpell
+  syn match podItalicAlternativeDelimOpen  "I<<\%(\s\+\|$\)" contains=@NoSpell
+  syn match podNoSpaceAlternativeDelimOpen "S<<\%(\s\+\|$\)" contains=@NoSpell
+  syn match podIndexAlternativeDelimOpen   "X<<\%(\s\+\|$\)" contains=@NoSpell
 
   " Add support for spell checking text inside B<>, I<>, S<> and X<>.
-  syn region podBold start="B<[^<]"me=e end=">" oneline contains=podBoldItalic,podBoldOpen
-  syn region podBoldAlternativeDelim start="B<<\s" end="\s>>" oneline contains=podBoldAlternativeDelimOpen
+  syn region podBold start="B<[^<]"me=e end=">" contains=podBoldItalic,podBoldOpen
+  syn region podBoldAlternativeDelim start="B<<\%(\s\+\|$\)" end="\%(\s\+\|^\)>>" contains=podBoldAlternativeDelimOpen
 
-  syn region podItalic start="I<[^<]"me=e end=">" oneline contains=podItalicBold,podItalicOpen
-  syn region podItalicAlternativeDelim start="I<<\s" end="\s>>" oneline contains=podItalicAlternativeDelimOpen
+  syn region podItalic start="I<[^<]"me=e end=">" contains=podItalicBold,podItalicOpen
+  syn region podItalicAlternativeDelim start="I<<\%(\s\+\|$\)" end="\%(\s\+\|^\)>>" contains=podItalicAlternativeDelimOpen
 
   " Nested bold/italic and vice-versa
-  syn region podBoldItalic contained start="I<[^<]"me=e end=">" oneline
-  syn region podItalicBold contained start="B<[^<]"me=e end=">" oneline
+  syn region podBoldItalic contained start="I<[^<]"me=e end=">"
+  syn region podItalicBold contained start="B<[^<]"me=e end=">"
 
-  syn region podNoSpace start="S<[^<]"ms=s-2 end=">"me=e oneline contains=podNoSpaceOpen
-  syn region podNoSpaceAlternativeDelim start="S<<\s"ms=s-2 end="\s>>"me=e oneline contains=podNoSpaceAlternativeDelimOpen
+  syn region podNoSpace start="S<[^<]"ms=s-2 end=">"me=e contains=podNoSpaceOpen
+  syn region podNoSpaceAlternativeDelim start="S<<\%(\s\+\|$\)"ms=s-2 end="\%(\s\+\|^\)>>"me=e contains=podNoSpaceAlternativeDelimOpen
 
-  syn region podIndex start="X<[^<]"ms=s-2 end=">"me=e oneline contains=podIndexOpen
-  syn region podIndexAlternativeDelim start="X<<\s"ms=s-2 end="\s>>"me=e oneline contains=podIndexAlternativeDelimOpen
+  syn region podIndex start="X<[^<]"ms=s-2 end=">"me=e contains=podIndexOpen
+  syn region podIndexAlternativeDelim start="X<<\%(\s\+\|$\)"ms=s-2 end="\%(\s\+\|^\)>>"me=e contains=podIndexAlternativeDelimOpen
 
   " Restore this (otherwise B<> is shown as bold inside verbatim)
-  syn match podVerbatimLine	"^\s.*$" contains=@NoSpell
+  syn region podVerbatim start="^\s\+\S.*$" end="^\ze\s*$" end="^\ze=cut\>" contains=@NoSpell
 
   " Ensure formatted text can be displayed in headings and items
   syn clear podCmdText
 
   if exists("perl_pod_spellcheck_headings")
-    syn match podCmdText ".*$" contained contains=podFormat,podBold,
+    syn match podCmdText ".*$" contained contains=@podFormat,podBold,
           \podBoldAlternativeDelim,podItalic,podItalicAlternativeDelim,
           \podBoldOpen,podItalicOpen,podBoldAlternativeDelimOpen,
           \podItalicAlternativeDelimOpen,podNoSpaceOpen
   else
-    syn match podCmdText ".*$" contained contains=podFormat,podBold,
+    syn match podCmdText ".*$" contained contains=@podFormat,podBold,
           \podBoldAlternativeDelim,podItalic,podItalicAlternativeDelim,
           \@NoSpell
   endif
@@ -172,4 +219,4 @@ let b:current_syntax = "pod"
 let &cpo = s:cpo_save
 unlet s:cpo_save
 
-" vim: ts=8
+" vim: ts=8 fdm=marker:
diff --git a/runtime/syntax/tap.vim b/runtime/syntax/tap.vim
index db37bb8980..6b00b1d588 100644
--- a/runtime/syntax/tap.vim
+++ b/runtime/syntax/tap.vim
@@ -2,9 +2,9 @@
 " Language:    Verbose TAP Output
 " Maintainer:  Rufus Cable <rufus@threebytesfull.com>
 " Remark:      Simple syntax highlighting for TAP output
-" License:
+" License:     Vim License (see :help license)
 " Copyright:   (c) 2008-2013 Rufus Cable
-" Last Change: 2014-12-13
+" Last Change: 2020 Mar 15
 
 if exists("b:current_syntax")
   finish
@@ -29,12 +29,12 @@ syn match tapTestStatusOK /ok/ contained
 syn match tapTestStatusNotOK /not ok/ contained
 
 " highlight todo tests
-syn match tapTestTodo /\(# TODO\|Failed (TODO)\) .*$/ contained contains=tapTestTodoRev
-syn match tapTestTodoRev /\<TODO\>/ contained
+syn match tapTestTodo /\c\(# TODO\|Failed (TODO)\) .*$/ contained contains=tapTestTodoRev
+syn match tapTestTodoRev /\c\<TODO\>/ contained
 
 " highlight skipped tests
-syn match tapTestSkip /# skip .*$/ contained contains=tapTestSkipTag
-syn match tapTestSkipTag /\(# \)\@<=skip\>/ contained
+syn match tapTestSkip /\c# skip .*$/ contained contains=tapTestSkipTag
+syn match tapTestSkipTag /\c\(# \)\@<=skip\>/ contained
 
 " look behind so "ok 123" and "not ok 124" match test number
 syn match tapTestNumber /\(ok \)\@<=\d\d*/ contained
@@ -51,17 +51,6 @@ syn region tapTestResultsSummaryNotOK start=/TODO passed:/ end=/$/ contained
 
 syn region tapTestInstructionsRegion start=/\%1l/ end=/^$/
 
-set foldtext=TAPTestLine_foldtext()
-function! TAPTestLine_foldtext()
-    let line = getline(v:foldstart)
-    let sub = substitute(line, '/\*\|\*/\|{{{\d\=', '', 'g')
-    return sub
-endfunction
-
-set foldminlines=5
-set foldcolumn=2
-set foldenable
-set foldmethod=syntax
 syn sync fromstart
 
 if !exists("did_tapverboseoutput_syntax_inits")
diff --git a/runtime/syntax/tt2.vim b/runtime/syntax/tt2.vim
index 6432b85a05..6826fb1581 100644
--- a/runtime/syntax/tt2.vim
+++ b/runtime/syntax/tt2.vim
@@ -1,9 +1,11 @@
+" Vim syntax file
 " Language:      TT2 (Perl Template Toolkit)
 " Maintainer:    vim-perl <vim-perl@googlegroups.com>
 " Author:        Moriki, Atsushi <4woods+vim@gmail.com>
-" Homepage:      http://github.com/vim-perl/vim-perl
-" Bugs/requests: http://github.com/vim-perl/vim-perl/issues
-" Last Change:   2015-04-25
+" Homepage:      https://github.com/vim-perl/vim-perl
+" Bugs/requests: https://github.com/vim-perl/vim-perl/issues
+" License:       Vim License (see :help license)
+" Last Change:   2018 Mar 28
 "
 " Installation:
 "   put tt2.vim and tt2html.vim in to your syntax directory.
@@ -42,9 +44,6 @@
 "               Release
 "           0.1.0
 "               Internal
-"
-" License: follow Vim :help uganda
-"
 
 if !exists("b:tt2_syn_tags")
     let b:tt2_syn_tags = '\[% %]'
@@ -95,7 +94,7 @@ if exists("b:tt2_syn_tags")
 
         "Include Perl syntax when 'PERL' 'RAWPERL' block
         if b:tt2_syn_inc_perl
-            syn include @Perl $VIMRUNTIME/syntax/perl.vim
+            syn include @Perl syntax/perl.vim
             exec 'syn region tt2_perlcode '.
                         \ 'start=+\(\(RAW\)\=PERL\s*[-]\=' . s:ed . '\(\n\)\=\)\@<=+ ' .
                         \ 'end=+' . s:st . '[-]\=\s*END+me=s-1 contains=@Perl keepend'
@@ -122,7 +121,7 @@ else
 
     "Include Perl syntax when 'PERL' 'RAWPERL' block
     if b:tt2_syn_inc_perl
-        syn include @Perl $VIMRUNTIME/syntax/perl.vim
+        syn include @Perl syntax/perl.vim
         syn region tt2_perlcode
                     \ start=+\(\(RAW\)\=PERL\s*[-]\=%]\(\n\)\=\)\@<=+
                     \ end=+\[%[-]\=\s*END+me=s-1
@@ -155,7 +154,7 @@ syn match   tt2_operator  "[!=<>]=\=\|&&\|||"               contained
 syn match   tt2_operator  "\(\s\)\@<=_\(\s\)\@="            contained
 syn match   tt2_operator  "=>\|,"                           contained
 syn match   tt2_deref     "\([[:alnum:]_)\]}]\s*\)\@<=\."   contained
-syn match   tt2_comment   +#.*$+                            contained extend
+syn match   tt2_comment   +#.*$+                            contained
 syn match   tt2_func      +\<\I\w*\(\s*(\)\@=+              contained nextgroup=tt2_bracket_r skipempty skipwhite
 "
 syn region  tt2_bracket_r  start=+(+ end=+)+                contained contains=@tt2_statement_cluster keepend extend
diff --git a/runtime/syntax/tt2html.vim b/runtime/syntax/tt2html.vim
index ac5744f39d..8c223be707 100644
--- a/runtime/syntax/tt2html.vim
+++ b/runtime/syntax/tt2html.vim
@@ -1,9 +1,11 @@
+" Vim syntax file
 " Language:      TT2 embedded with HTML
 " Maintainer:    vim-perl <vim-perl@googlegroups.com>
 " Author:        Moriki, Atsushi <4woods+vim@gmail.com>
-" Homepage:      http://github.com/vim-perl/vim-perl
-" Bugs/requests: http://github.com/vim-perl/vim-perl/issues
-" Last Change:   2013-07-21
+" Homepage:      https://github.com/vim-perl/vim-perl
+" Bugs/requests: https://github.com/vim-perl/vim-perl/issues
+" License:       Vim License (see :help license)
+" Last Change:   2018 Mar 28
 
 if exists("b:current_syntax")
     finish
diff --git a/runtime/syntax/tt2js.vim b/runtime/syntax/tt2js.vim
index 350df57d4c..52e5a3c54a 100644
--- a/runtime/syntax/tt2js.vim
+++ b/runtime/syntax/tt2js.vim
@@ -1,9 +1,11 @@
+" Vim syntax file
 " Language:      TT2 embedded with Javascript
 " Maintainer:    Andy Lester <andy@petdance.com>
 " Author:        Yates, Peter <pd.yates@gmail.com>
-" Homepage:      http://github.com/vim-perl/vim-perl
-" Bugs/requests: http://github.com/vim-perl/vim-perl/issues
-" Last Change:   2013-07-21
+" Homepage:      https://github.com/vim-perl/vim-perl
+" Bugs/requests: https://github.com/vim-perl/vim-perl/issues
+" License:       Vim License (see :help license)
+" Last Change:   2018 Mar 28
 
 if exists("b:current_syntax")
     finish
diff --git a/runtime/syntax/vim.vim b/runtime/syntax/vim.vim
index dc7ef51b2f..0eec9f13de 100644
--- a/runtime/syntax/vim.vim
+++ b/runtime/syntax/vim.vim
@@ -435,12 +435,11 @@ syn case match
 " User Function Highlighting: {{{2
 " (following Gautam Iyer's suggestion)
 " ==========================
-syn match vimFunc		"\%(\%([sSgGbBwWtTlL]:\|<[sS][iI][dD]>\)\=\%(\w\+\.\)*\I[a-zA-Z0-9_.]*\)\ze\s*("		contains=vimFuncEcho,vimFuncName,vimUserFunc,vimExecute
+syn match vimFunc		"\%(\%([sSgGbBwWtTlL]:\|<[sS][iI][dD]>\)\=\%(\w\+\.\)*\I[a-zA-Z0-9_.]*\)\ze\s*("		contains=vimCommand,vimFuncEcho,vimFuncName,vimUserFunc,vimExecute
 syn match vimUserFunc contained	"\%(\%([sSgGbBwWtTlL]:\|<[sS][iI][dD]>\)\=\%(\w\+\.\)*\I[a-zA-Z0-9_.]*\)\|\<\u[a-zA-Z0-9.]*\>\|\<if\>"	contains=vimCommand,vimNotation
 syn keyword vimFuncEcho contained	ec ech echo
 
 " User Command Highlighting: {{{2
-"syn match vimUsrCmd	'^\s*\zs\u\w*.*$'
 syn match vimUsrCmd	'^\s*\zs\u\%(\w*\)\@>\%([(#[]\|\s\+\%([-+*/%]\=\|\.\.\)=\)\@!'
 
 " Errors And Warnings: {{{2
diff --git a/runtime/syntax/xs.vim b/runtime/syntax/xs.vim
index 3e658b4a83..2145ede2dd 100644
--- a/runtime/syntax/xs.vim
+++ b/runtime/syntax/xs.vim
@@ -1,9 +1,12 @@
 " Vim syntax file
-" Language:    XS (Perl extension interface language)
-" Author:      Autogenerated from perl headers, on an original basis of Michael W. Dodge <sarge@pobox.com>
-" Maintainer:  vim-perl <vim-perl@googlegroups.com>
-" Previous:    Vincent Pit <perl@profvince.com>
-" Last Change: 2017-09-12
+" Language:      XS (Perl extension interface language)
+" Author:        Autogenerated from perl headers, on an original basis of Michael W. Dodge <sarge@pobox.com>
+" Maintainer:    vim-perl <vim-perl@googlegroups.com>
+" Previous:      Vincent Pit <perl@profvince.com>
+" Homepage:      https://github.com/vim-perl/vim-perl
+" Bugs/requests: https://github.com/vim-perl/vim-perl/issues
+" License:       Vim License (see :help license)
+" Last Change:   2018 Mar 28
 
 if exists("b:current_syntax")
   finish