diff --git a/runtime/indent/dtd.vim b/runtime/indent/dtd.vim
index c2b3c0c..9fca296 100644
--- a/runtime/indent/dtd.vim
+++ b/runtime/indent/dtd.vim
@@ -4,6 +4,12 @@
 " Previous Maintainer:	Nikolai Weibull <now@bitwi.se>
 " Last Change:		24 Sep 2021
 
+" Only load this indent file when no other was loaded.
+if exists("b:did_indent")
+  finish
+endif
+let b:did_indent = 1
+
 setlocal indentexpr=GetDTDIndent()
 setlocal indentkeys=!^F,o,O,>
 setlocal nosmartindent
diff --git a/runtime/indent/julia.vim b/runtime/indent/julia.vim
index a90cff4..8e4c603 100644
--- a/runtime/indent/julia.vim
+++ b/runtime/indent/julia.vim
@@ -2,9 +2,15 @@
 " Language:	Julia
 " Maintainer:	Carlo Baldassi <carlobaldassi@gmail.com>
 " Homepage:	https://github.com/JuliaEditorSupport/julia-vim
-" Last Change:	2016 jun 16
+" Last Change:	2022 Jun 14
 " Notes:        originally based on Bram Molenaar's indent file for vim
 
+" Only load this indent file when no other was loaded.
+if exists("b:did_indent")
+  finish
+endif
+let b:did_indent = 1
+
 setlocal autoindent
 
 setlocal indentexpr=GetJuliaIndent()
diff --git a/runtime/indent/perl.vim b/runtime/indent/perl.vim
index b107a72..4c91fa1 100644
--- a/runtime/indent/perl.vim
+++ b/runtime/indent/perl.vim
@@ -6,104 +6,178 @@
 " License:       Vim License (see :help license)
 " Last Change:   2021 Sep 24
 
-if exists("b:did_ftplugin") | finish | endif
-let b:did_ftplugin = 1
+" Suggestions and improvements by :
+"   Aaron J. Sherman (use syntax for hints)
+"   Artem Chuprina (play nice with folding)
 
-" Make sure the continuation lines below do not cause problems in
-" compatibility mode.
-let s:save_cpo = &cpo
+" TODO things that are not or not properly indented (yet) :
+" - Continued statements
+"     print "foo",
+"       "bar";
+"     print "foo"
+"       if bar();
+" - Multiline regular expressions (m//x)
+" (The following probably needs modifying the perl syntax file)
+" - qw() lists
+" - Heredocs with terminators that don't match \I\i*
+
+" Only load this indent file when no other was loaded.
+if exists("b:did_indent")
+    finish
+endif
+let b:did_indent = 1
+
+" Is syntax highlighting active ?
+let b:indent_use_syntax = has("syntax")
+
+setlocal indentexpr=GetPerlIndent()
+setlocal indentkeys+=0=,0),0],0=or,0=and
+if !b:indent_use_syntax
+    setlocal indentkeys+=0=EO
+endif
+
+let b:undo_indent = "setl inde< indk<"
+
+let s:cpo_save = &cpo
 set cpo-=C
 
-setlocal formatoptions-=t
-setlocal formatoptions+=crqol
-setlocal keywordprg=perldoc\ -f
+function! GetPerlIndent()
 
-setlocal comments=:#
-setlocal commentstring=#%s
+    " Get the line to be indented
+    let cline = getline(v:lnum)
 
-" Provided by Ned Konz <ned at bike-nomad dot com>
-"---------------------------------------------
-setlocal include=\\<\\(use\\\|require\\)\\>
-" '+' is removed to support plugins in Catalyst or DBIx::Class
-" where the leading plus indicates a fully-qualified module name.
-setlocal includeexpr=substitute(substitute(substitute(substitute(v:fname,'+','',''),'::','/','g'),'->\*','',''),'$','.pm','')
-setlocal define=[^A-Za-z_]
-setlocal iskeyword+=:
-
-" The following line changes a global variable but is necessary to make
-" gf and similar commands work. Thanks to Andrew Pimlott for pointing
-" out the problem.
-let s:old_isfname = &isfname
-set isfname+=:
-let s:new_isfname = &isfname
-
-augroup perl_global_options
-  au!
-  exe "au BufEnter * if &filetype == 'perl' | let &isfname = '" . s:new_isfname . "' | endif"
-  exe "au BufLeave * if &filetype == 'perl' | let &isfname = '" . s:old_isfname . "' | endif"
-augroup END
-
-" Undo the stuff we changed.
-let b:undo_ftplugin = "setlocal fo< kp< com< cms< inc< inex< def< isk<" .
-      \               " | let &isfname = '" .  s:old_isfname . "'"
-
-if get(g:, 'perl_fold', 0)
-  setlocal foldmethod=syntax
-  let b:undo_ftplugin .= " | setlocal fdm<"
-endif
-
-" Set this once, globally.
-if !exists("perlpath")
-    if executable("perl")
-      try
-	if &shellxquote != '"'
-	    let perlpath = system('perl -e "print join(q/,/,@INC)"')
-	else
-	    let perlpath = system("perl -e 'print join(q/,/,@INC)'")
-	endif
-	let perlpath = substitute(perlpath,',.$',',,','')
-      catch /E145:/
-	let perlpath = ".,,"
-      endtry
-    else
-	" If we can't call perl to get its path, just default to using the
-	" current directory and the directory of the current file.
-	let perlpath = ".,,"
+    " Indent POD markers to column 0
+    if cline =~ '^\s*=\L\@!'
+        return 0
     endif
-endif
 
-" Append perlpath to the existing path value, if it is set.  Since we don't
-" use += to do it because of the commas in perlpath, we have to handle the
-" global / local settings, too.
-if &l:path == ""
-    if &g:path == ""
-        let &l:path=perlpath
-    else
-        let &l:path=&g:path.",".perlpath
+    " Get current syntax item at the line's first char
+    let csynid = ''
+    if b:indent_use_syntax
+        let csynid = synIDattr(synID(v:lnum,1,0),"name")
     endif
-else
-    let &l:path=&l:path.",".perlpath
-endif
 
-let b:undo_ftplugin .= " | setlocal pa<"
-"---------------------------------------------
+    " Don't reindent POD and heredocs
+    if csynid == "perlPOD" || csynid == "perlHereDoc" || csynid =~ "^pod"
+        return indent(v:lnum)
+    endif
 
-" Change the browse dialog to show mainly Perl-related files
-if (has("gui_win32") || has("gui_gtk")) && !exists("b:browsefilter")
-    let b:browsefilter = "Perl Source Files (*.pl)\t*.pl\n" .
-		       \ "Perl Modules (*.pm)\t*.pm\n" .
-		       \ "Perl Documentation Files (*.pod)\t*.pod\n" .
-		       \ "All Files (*.*)\t*.*\n"
-    let b:undo_ftplugin .= " | unlet! b:browsefilter"
-endif
+    " Indent end-of-heredocs markers to column 0
+    if b:indent_use_syntax
+        " Assumes that an end-of-heredoc marker matches \I\i* to avoid
+        " confusion with other types of strings
+        if csynid == "perlStringStartEnd" && cline =~ '^\I\i*$'
+            return 0
+        endif
+    else
+        " Without syntax hints, assume that end-of-heredocs markers begin with EO
+        if cline =~ '^\s*EO'
+            return 0
+        endif
+    endif
 
-" Proper matching for matchit plugin
-if exists("loaded_matchit") && !exists("b:match_words")
-    let b:match_skip = 's:comment\|string\|perlQQ\|perlShellCommand\|perlHereDoc\|perlSubstitution\|perlTranslation\|perlMatch\|perlFormatField'
-    let b:match_words = '\<if\>:\<elsif\>:\<else\>'
-    let b:undo_ftplugin .= " | unlet! b:match_words b:match_skip"
-endif
+    " Now get the indent of the previous perl line.
 
-" Restore the saved compatibility options.
-let &cpo = s:save_cpo
-unlet s:save_cpo s:old_isfname s:new_isfname
+    " Find a non-blank line above the current line.
+    let lnum = prevnonblank(v:lnum - 1)
+    " Hit the start of the file, use zero indent.
+    if lnum == 0
+        return 0
+    endif
+    let line = getline(lnum)
+    let ind = indent(lnum)
+    " Skip heredocs, POD, and comments on 1st column
+    if b:indent_use_syntax
+        let skippin = 2
+        while skippin
+            let synid = synIDattr(synID(lnum,1,0),"name")
+            if (synid == "perlStringStartEnd" && line =~ '^\I\i*$')
+                        \ || (skippin != 2 && synid == "perlPOD")
+                        \ || (skippin != 2 && synid == "perlHereDoc")
+                        \ || synid == "perlComment"
+                        \ || synid =~ "^pod"
+                let lnum = prevnonblank(lnum - 1)
+                if lnum == 0
+                    return 0
+                endif
+                let line = getline(lnum)
+                let ind = indent(lnum)
+                let skippin = 1
+            else
+                let skippin = 0
+            endif
+        endwhile
+    else
+        if line =~ "^EO"
+            let lnum = search("<<[\"']\\=EO", "bW")
+            let line = getline(lnum)
+            let ind = indent(lnum)
+        endif
+    endif
+
+    " Indent blocks enclosed by {}, (), or []
+    if b:indent_use_syntax
+        " Find a real opening brace
+        " NOTE: Unlike Perl character classes, we do NOT need to escape the
+        " closing brackets with a backslash.  Doing so just puts a backslash
+        " in the character class and causes sorrow.  Instead, put the closing
+        " bracket as the first character in the class.
+        let braceclass = '[][(){}]'
+        let bracepos = match(line, braceclass, matchend(line, '^\s*[])}]'))
+        while bracepos != -1
+            let synid = synIDattr(synID(lnum, bracepos + 1, 0), "name")
+            " If the brace is highlighted in one of those groups, indent it.
+            " 'perlHereDoc' is here only to handle the case '&foo(<<EOF)'.
+            if synid == ""
+                        \ || synid == "perlMatchStartEnd"
+                        \ || synid == "perlHereDoc"
+                        \ || synid == "perlBraces"
+                        \ || synid == "perlStatementIndirObj"
+                        \ || synid =~ "^perlFiledescStatement"
+                        \ || synid =~ '^perl\(Sub\|Block\|Package\)Fold'
+                let brace = strpart(line, bracepos, 1)
+                if brace == '(' || brace == '{' || brace == '['
+                    let ind = ind + shiftwidth()
+                else
+                    let ind = ind - shiftwidth()
+                endif
+            endif
+            let bracepos = match(line, braceclass, bracepos + 1)
+        endwhile
+        let bracepos = matchend(cline, '^\s*[])}]')
+        if bracepos != -1
+            let synid = synIDattr(synID(v:lnum, bracepos, 0), "name")
+            if synid == ""
+                        \ || synid == "perlMatchStartEnd"
+                        \ || synid == "perlBraces"
+                        \ || synid == "perlStatementIndirObj"
+                        \ || synid =~ '^perl\(Sub\|Block\|Package\)Fold'
+                let ind = ind - shiftwidth()
+            endif
+        endif
+    else
+        if line =~ '[{[(]\s*\(#[^])}]*\)\=$'
+            let ind = ind + shiftwidth()
+        endif
+        if cline =~ '^\s*[])}]'
+            let ind = ind - shiftwidth()
+        endif
+    endif
+
+    " Indent lines that begin with 'or' or 'and'
+    if cline =~ '^\s*\(or\|and\)\>'
+        if line !~ '^\s*\(or\|and\)\>'
+            let ind = ind + shiftwidth()
+        endif
+    elseif line =~ '^\s*\(or\|and\)\>'
+        let ind = ind - shiftwidth()
+    endif
+
+    return ind
+
+endfunction
+
+let &cpo = s:cpo_save
+unlet s:cpo_save
+
+" vim:ts=8:sts=4:sw=4:expandtab:ft=vim