Update runtime files.

24 files changed, 480 insertions, 161 deletions

diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
index 7401f419f8..970cc942dc 100644
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -164,6 +164,7 @@ runtime/syntax/nsis.vim			@k-takata
 runtime/syntax/pdf.vim			@tpope
 runtime/syntax/php.vim			@TysonAndre
 runtime/syntax/privoxy.vim		@dkearns
+runtime/syntax/prolog.vim		@XVilka
 runtime/syntax/rc.vim			@chrisbra
 runtime/syntax/rpcgen.vim		@cecamp
 runtime/syntax/ruby.vim			@dkearns
diff --git a/runtime/doc/editing.txt b/runtime/doc/editing.txt
index 7f30e54ae3..4c4de79ee3 100644
--- a/runtime/doc/editing.txt
+++ b/runtime/doc/editing.txt
@@ -1,4 +1,4 @@
-*editing.txt*   For Vim version 8.2.  Last change: 2020 Dec 19
+*editing.txt*   For Vim version 8.2.  Last change: 2021 Jan 08
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -1014,7 +1014,7 @@ to write anyway add a '!' to the command.
 
 							*write-permissions*
 When writing a new file the permissions are read-write.  For unix the mask is
-0666 with additionally umask applied.  When writing a file that was read Vim
+0o666 with additionally umask applied.  When writing a file that was read Vim
 will preserve the permissions, but clear the s-bit.
 
 							*write-readonly*
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 4d26df86ef..2963193a00 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1,4 +1,4 @@
-*options.txt*	For Vim version 8.2.  Last change: 2020 Dec 21
+*options.txt*	For Vim version 8.2.  Last change: 2021 Jan 08
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -438,7 +438,7 @@ the system, mostly it is something like 256 or 1024 characters.
 				  CTRL-?	CTRL-H
 				not CTRL-?	CTRL-?
 
-			(CTRL-? is 0177 octal, 0x7f hex)
+			(CTRL-? is 0o177 octal, 0x7f hex)
 
 			If your delete key terminal code is wrong, but the
 			code for backspace is alright, you can put this in
diff --git a/runtime/doc/os_vms.txt b/runtime/doc/os_vms.txt
index f5c48590e5..6eb2993bc7 100644
--- a/runtime/doc/os_vms.txt
+++ b/runtime/doc/os_vms.txt
@@ -1,4 +1,4 @@
-*os_vms.txt*    For Vim version 8.2.  Last change: 2020 Dec 30
+*os_vms.txt*    For Vim version 8.2.  Last change: 2021 Jan 04
 
 
 		  VIM REFERENCE MANUAL
@@ -767,8 +767,10 @@ GNU_TOOLS.ZIP package downloadable from http://www.polarhome.com/vim/
 
 Version 8.2
 - make all changes needed for clean compile build of v8.2 on VMS on all platforms
-- test on VSI OpenVMS platforms
-- added  XPM support - Motif GUI with toolbar on all platforms
+- fix the call mkdir bug (vicente_polo@yahoo.es) 
+- test on VSI OpenVMS Alpha and Itanium platforms
+- added LUA support
+- added XPM support - Motif GUI with toolbar on all platforms
 - XPM v3.4.11 libraries for IA64, AXP and VAX are added 
 - start integrating the new test scripts 
 
diff --git a/runtime/doc/pattern.txt b/runtime/doc/pattern.txt
index 177a652b76..82b4418be6 100644
--- a/runtime/doc/pattern.txt
+++ b/runtime/doc/pattern.txt
@@ -1,4 +1,4 @@
-*pattern.txt*   For Vim version 8.2.  Last change: 2020 Dec 25
+*pattern.txt*   For Vim version 8.2.  Last change: 2021 Jan 08
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -1179,7 +1179,7 @@ x	A single character, with no special meaning, matches itself
 		\b	<BS>
 		\n	line break, see above |/[\n]|
 		\d123	decimal number of character
-		\o40	octal number of character up to 0377
+		\o40	octal number of character up to 0o377
 		\x20	hexadecimal number of character up to 0xff
 		\u20AC	hex. number of multibyte character up to 0xffff
 		\U1234	hex. number of multibyte character up to 0xffffffff
@@ -1217,7 +1217,8 @@ x	A single character, with no special meaning, matches itself
 \%d123	Matches the character specified with a decimal number.  Must be
 	followed by a non-digit.
 \%o40	Matches the character specified with an octal number up to 0377.
-	Numbers below 040 must be followed by a non-octal digit or a non-digit.
+	Numbers below 0o40 must be followed by a non-octal digit or a
+	non-digit.
 \%x2a	Matches the character specified with up to two hexadecimal characters.
 \%u20AC	Matches the character specified with up to four hexadecimal
 	characters.
diff --git a/runtime/doc/tags b/runtime/doc/tags
index a32731db86..1b36eb2984 100644
--- a/runtime/doc/tags
+++ b/runtime/doc/tags
@@ -1783,6 +1783,8 @@ $VIM_POSIX	vi_diff.txt	/*$VIM_POSIX*
 09.2	usr_09.txt	/*09.2*
 09.3	usr_09.txt	/*09.3*
 09.4	usr_09.txt	/*09.4*
+0o	eval.txt	/*0o*
+0x	eval.txt	/*0x*
 10.1	usr_10.txt	/*10.1*
 10.2	usr_10.txt	/*10.2*
 10.3	usr_10.txt	/*10.3*
@@ -1994,6 +1996,7 @@ $VIM_POSIX	vi_diff.txt	/*$VIM_POSIX*
 :AdaTagFile	ft_ada.txt	/*:AdaTagFile*
 :AdaTypes	ft_ada.txt	/*:AdaTypes*
 :Arguments	terminal.txt	/*:Arguments*
+:Asm	terminal.txt	/*:Asm*
 :Break	terminal.txt	/*:Break*
 :Cfilter	quickfix.txt	/*:Cfilter*
 :Clear	terminal.txt	/*:Clear*
@@ -5756,6 +5759,7 @@ characterwise	motion.txt	/*characterwise*
 characterwise-register	change.txt	/*characterwise-register*
 characterwise-visual	visual.txt	/*characterwise-visual*
 charclass()	eval.txt	/*charclass()*
+charcol()	eval.txt	/*charcol()*
 charconvert_from-variable	eval.txt	/*charconvert_from-variable*
 charconvert_to-variable	eval.txt	/*charconvert_to-variable*
 charidx()	eval.txt	/*charidx()*
@@ -6951,6 +6955,7 @@ getbufvar()	eval.txt	/*getbufvar()*
 getchangelist()	eval.txt	/*getchangelist()*
 getchar()	eval.txt	/*getchar()*
 getcharmod()	eval.txt	/*getcharmod()*
+getcharpos()	eval.txt	/*getcharpos()*
 getcharsearch()	eval.txt	/*getcharsearch()*
 getcmdline()	eval.txt	/*getcmdline()*
 getcmdpos()	eval.txt	/*getcmdpos()*
@@ -6958,6 +6963,7 @@ getcmdtype()	eval.txt	/*getcmdtype()*
 getcmdwintype()	eval.txt	/*getcmdwintype()*
 getcompletion()	eval.txt	/*getcompletion()*
 getcurpos()	eval.txt	/*getcurpos()*
+getcursorcharpos()	eval.txt	/*getcursorcharpos()*
 getcwd()	eval.txt	/*getcwd()*
 getenv()	eval.txt	/*getenv()*
 getfontname()	eval.txt	/*getfontname()*
@@ -8260,6 +8266,7 @@ notation	intro.txt	/*notation*
 notepad	gui_w32.txt	/*notepad*
 nr2char()	eval.txt	/*nr2char()*
 nroff.vim	syntax.txt	/*nroff.vim*
+null	vim9.txt	/*null*
 null-variable	eval.txt	/*null-variable*
 number_relativenumber	options.txt	/*number_relativenumber*
 numbered-function	eval.txt	/*numbered-function*
@@ -8871,8 +8878,10 @@ set-spc-auto	spell.txt	/*set-spc-auto*
 setbufline()	eval.txt	/*setbufline()*
 setbufvar()	eval.txt	/*setbufvar()*
 setcellwidths()	eval.txt	/*setcellwidths()*
+setcharpos()	eval.txt	/*setcharpos()*
 setcharsearch()	eval.txt	/*setcharsearch()*
 setcmdpos()	eval.txt	/*setcmdpos()*
+setcursorcharpos()	eval.txt	/*setcursorcharpos()*
 setenv()	eval.txt	/*setenv()*
 setfperm()	eval.txt	/*setfperm()*
 setline()	eval.txt	/*setline()*
@@ -9553,6 +9562,7 @@ termdebug-prompt	terminal.txt	/*termdebug-prompt*
 termdebug-starting	terminal.txt	/*termdebug-starting*
 termdebug-stepping	terminal.txt	/*termdebug-stepping*
 termdebug-variables	terminal.txt	/*termdebug-variables*
+termdebug_disasm_window	terminal.txt	/*termdebug_disasm_window*
 termdebug_map_K	terminal.txt	/*termdebug_map_K*
 termdebug_popup	terminal.txt	/*termdebug_popup*
 termdebug_shortcuts	terminal.txt	/*termdebug_shortcuts*
@@ -10086,6 +10096,7 @@ vim9-reload	vim9.txt	/*vim9-reload*
 vim9-scopes	vim9.txt	/*vim9-scopes*
 vim9-script-intro	usr_46.txt	/*vim9-script-intro*
 vim9-types	vim9.txt	/*vim9-types*
+vim9-user-command	vim9.txt	/*vim9-user-command*
 vim9.txt	vim9.txt	/*vim9.txt*
 vim9script	vim9.txt	/*vim9script*
 vim:	options.txt	/*vim:*
diff --git a/runtime/doc/terminal.txt b/runtime/doc/terminal.txt
index 195122910a..5885cb1976 100644
--- a/runtime/doc/terminal.txt
+++ b/runtime/doc/terminal.txt
@@ -1,4 +1,4 @@
-*terminal.txt*	For Vim version 8.2.  Last change: 2020 Dec 28
+*terminal.txt*	For Vim version 8.2.  Last change: 2021 Jan 04
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -1330,6 +1330,8 @@ Other commands ~
  *:Program*    jump to the window with the running program
  *:Source*     jump to the window with the source code, create it if there
 	     isn't one
+ *:Asm*	     jump to the window with the disassembly, create it if there
+	     isn't one
 
 
 Prompt mode ~
@@ -1352,6 +1354,12 @@ Prompt mode can be used even when the |+terminal| feature is present with: >
 The K key is normally mapped to :Evaluate. If you do not want this use: >
 	let g:termdebug_map_K = 0
 
+<
+						*termdebug_disasm_window*
+If you want the Asm window shown by default, set this to 1. Setting to
+any value greater than 1 will set the Asm window height to that value: >
+	let g:termdebug_disasm_window = 15
+<
 
 Communication ~
 						*termdebug-communication*
diff --git a/runtime/doc/todo.txt b/runtime/doc/todo.txt
index 07779b470e..6e5fe4cc09 100644
--- a/runtime/doc/todo.txt
+++ b/runtime/doc/todo.txt
@@ -1,4 +1,4 @@
-*todo.txt*      For Vim version 8.2.  Last change: 2021 Jan 02
+*todo.txt*      For Vim version 8.2.  Last change: 2021 Jan 11
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -38,18 +38,29 @@ browser use: https://github.com/vim/vim/issues/1234
 							*known-bugs*
 -------------------- Known bugs and current work -----------------------
 
-Reload: How to make sure type of script function hasn't changed?
-
-Valgrind: test_vim9_cmd: uses uninitialized var
+no error for:
+  echo extend([0], ['a', true])
+like it does for:
+  echo extend([0], ['a'])
+At script level this does not give an error:
+  echo map([0], (_, v) => [])
+Or:
+  var l: list<number> = [0]
+  echo map(l, (_, v) => [])
 
 Vim9 - Make everything work:
+- Expand `=expr` in :next, :argedit, :argadd, :argdelete, :drop
+- Expand `=expr` in :vimgrep, :vimgrepadd, :lvimgrep, :lvimgrepadd
+- Expand `=expr` in :mkspell
+- Unlet with range: "unlet list[a : b]"
 - Implement "export {one, two three}".
-- Use "null" for v:null, like true and false?  #7495
 - ISN_CHECKTYPE could use check_argtype()
 - Using a script variable inside a :def function doesn't work if the variable
   is inside a block, see Test_nested_function().  Should it work?
 - give error for variable name:
       let p = function('NoSuchFunc')
+- Make closures work better:
+  - Create closure in a loop.  Need to make a list of them.
 - If a :def function is called with a function reference, compile it to get
   the function type.
 	def Filter(x: string, Cond: func(string): bool)
@@ -63,25 +74,18 @@ Vim9 - Make everything work:
 	    statement
 	    statement
 	}
-- implement { cmd } compiled
-- implement { cmd } at script level
-- Expand `=expr` in :next, :argedit, :argadd, :argdelete, :drop
-- Expand `=expr` in :vimgrep, :vimgrepadd, :lvimgrep, :lvimgrepadd
-- Expand `=expr` in :mkspell
 - Does this work already: can use func as reference:
 	def SomeFunc() ...
 	map(list, SomeFunc)
 - For builtin functions using tv_get_string*() use check_for_string() to be
   more strict about the argument type.
+- Possible memory leaks in test_vim9_func
 - Implement :lockvar and :unlockvar.  How about local variables?  Perhaps only
   allow this for global variables.  Use :final or :const otherwise.
 - Allow function names that will be script-local to start with lower case
   letter?  Or also require names with s: prefix to use upper case?
   Also apply this function references "var ref = SomeFunc"
 - Support passing v:none to use the default argument value. (#6504)
-- Make map() give an error if the resulting type of the first argument is
-  wrong.  Only works if the type is known?  Is this slow (need to go over all
-  items)?
 - Run the same tests in :def and Vim9 script, like in Test_expr7_not()
 - Check many more builtin function arguments at compile time.
 - make 0 == 'string' fail on the script level, like inside :def.
@@ -105,57 +109,59 @@ Vim9 - Make everything work:
 - Implement "as Name" in "import Item as Name from ..."
 - Implement using imported items at script level from "import * as X" in
   eval_variable().  Should pass the ".xxx" that follows and return that.
-- Disallow unlet for local/script/imported vars
 - Make "++nr" work.  "++g:count" doesn't work, thinks it is a range.
-- Make closures work:
-  - Create closure in a loop.  Need to make a list of them.
-  - nested closure only uses one context, not all (#7150)
+- Reload: How to make sure type of script function hasn't changed?
 - expandcmd() with `=expr` in filename uses legacy expression.
 - eval_expr() in ex_cexpr()
 - eval_expr() call in dbg_parsearg() and debuggy_find()
-Improve error checking:
-- "echo Func()" is an error if Func() does not return anything.
-Before launch:
+- compile "skip" argument of searchpair()
+- compile "expr" and "call" expression of a channel in channel_exe_cmd()?
+- give an error for "echo Func()" if Func() does not return anything.
+
+Once Vim9 is stable:
+- Change the help to prefer Vim9 syntax where appropriate
+- Use Vim9 for runtime files.
+    PR #7497 for autoload/ccomplete.vim
 - Add all the error numbers in a good place in documentation.
 - In the generic eval docs, point out the Vim9 syntax where it differs.
-Also:
-- For range: make table of first ASCII character with flag to quickly check if
-  it can be a Vim9 command. E.g. "+" can, but "." can't.
+
+Also for Vim9:
 - better implementation for partial and tests for that.
 - Make "g:imported = Export.exported" work in Vim9 script.
 - Make Foo.Bar() work to call the dict function. (#5676)
 - Error in any command in "vim9script" aborts sourcing.
 - Find a way to test expressions in legacy and Vim9 script without duplication
-- Test each level of expressions properly, with type checking
 - Test try/catch and throw better, also nested.
-  Test return inside try/finally jumps to finally and then returns.
+  Test that return inside try/finally jumps to finally and then returns.
 - Test that a function defined inside a :def function is local to that
   function, g: functions can be defined and script-local functions cannot be
   defined.
-- implement :type
-- import type declaration?
+- compile options that are an expression, e.g. "expr:" in 'spellsuggest',
+  'foldexpr', 'foldtext', 'printexpr', 'diffexpr', 'patchexpr', 'charconvert',
+  'balloonexpr', 'includeexpr', 'indentexpr', 'formatexpr'.
+  Give an error if compilation fails. (#7625)
+  Use the location where the option was set for deciding whether it's to be
+  evaluated in Vim9 script context.
+- implement :type; import type declaration.
+- implement enum;  import enum.
 - Future work: See |vim9-classes|
-- implement enum
-- Make accessing varargs faster: arg[expr]
-	EVAL expr
-	LOADVARARG (varargs idx)
+	Define the keywords and commands to make sure it will be backwards
+	compatible.
 - Make debugging work - at least per function.  Need to recompile a function
   to step through it line-by-line?  Evaluate the stack and variables on the
   stack?
 - Make profiling work - Add ISN_PROFILE instructions after every line?
 - List commands when 'verbose' is set or :verbose is used.
-Once Vim9 is stable:
-- Change the help to prefer Vim9 syntax where appropriate
-- Use Vim9 for runtime files.
-    PR #7497 for autoload/ccomplete.vim
-Further improvements:
-- compile options that are an expression, e.g. "expr:" in 'spellsuggest',
-  'foldexpr', 'foldtext', 'printexpr', 'diffexpr', 'patchexpr', 'charconvert',
-  'balloonexpr', 'includeexpr', 'indentexpr', 'formatexpr'.
+
+Further Vim9 improvements, possibly after launch:
+- For range: make table of first ASCII character with flag to quickly check if
+  it can be a Vim9 command. E.g. "+" can, but "." can't.
 - compile get_lambda_tv() in popup_add_timeout()
 - inline call to map() and filter()
-- compile "skip" argument of searchpair()
-- compile "expr" and "call" expression of a channel in channel_exe_cmd()?
+- Make accessing varargs faster: arg[expr]
+	EVAL expr
+	LOADVARARG (varargs idx)
+
 
 Popup windows:
 - Add a flag to make a popup window focusable?
@@ -308,6 +314,18 @@ Any way to convert "$" back by using a special value? (#6901)
 Can we detect true color support?  https://gist.github.com/XVilka/8346728
 Try setting a color then request the current color, like using t_u7.
 
+Regexp to search for duplicate lines does not work correctly:
+/\(^.*\n\)\1  (Chris Morgan, #6239)
+
+Changing a capturing group to non-capturing changes the result: #7607
+    :echo matchstr('aaa bbb', '\(.\{-1,}\>\)\|.*')
+    aaa
+    :echo matchstr('aaa bbb', '\%(.\{-1,}\>\)\|.*')
+    aaa bbb
+Should also work without any group:
+    :echo matchstr('aaa bbb', '.\{-1,}\>\|.*')
+    aaa bbb  (should be aaa)
+
 Check out PR #543 (Roland Puntaier).
 Patch for multibyte characters in langmap and applying a mapping on them.
 (Christian Brabandt, 2015 Jun 12, update July 25)
@@ -393,9 +411,6 @@ corruption.  (#6631)
 When 'lazyredraw' is set sometimes the title is not updated.
 (Jason Franklin, 2020 Feb 3)  Looks like a race condition.
 
-Regexp to search for duplicate lines does not work correctly:
-/\(^.*\n\)\1  (Chris Morgan, #6239)
-
 With bash ":make" does not set v:shell_error.  Possible solution: set
 'shellpipe' to "2>&1| tee %s; exit ${PIPESTATUS[0]}"  #5994
 
@@ -1152,7 +1167,7 @@ Overlong utf-8 sequence is displayed wrong. (Harm te Hennepe, 2017 Sep 14,
 #2089)  Patch with possible solution by Björn Linse.
 
 The change list index is local to a buffer, but it doesn't make sense using it
-for another buffer.  (lacygolil) Copy w_changelistidx to wininfo_S and back.
+for another buffer.  (lacygoill) Copy w_changelistidx to wininfo_S and back.
 
 X11: Putting more than about 262040 characters of text on the clipboard and
 pasting it in another Vim doesn't work.  (Dominique Pelle, 2008 Aug 21-23)
@@ -5474,7 +5489,7 @@ Mappings and Abbreviations:
     not the <Space>.
 8   Give a warning when using CTRL-C in the lhs of a mapping.  It will never
     (?) work.
-7   Add <0x8f> (hex), <033> (octal) and <123> (decimal) to <> notation?
+7   Add <0x8f> (hex), <0o33> (octal) and <123> (decimal) to <> notation?
 7   When someone tries to unmap with a trailing space, and it fails, try
     unmapping without the trailing space.  Helps for ":unmap xx | unmap yy".
 6   Context-sensitive abbreviations: Specify syntax group(s) in which the
diff --git a/runtime/doc/usr_03.txt b/runtime/doc/usr_03.txt
index c3bf2d312e..d30bddfc62 100644
--- a/runtime/doc/usr_03.txt
+++ b/runtime/doc/usr_03.txt
@@ -50,7 +50,7 @@ which moves to the previous end of a word:
 
 	This is a line with example text ~
 	   <----<----x---->------------>
-	   2ge   ge     e       we
+	   2ge   ge     e       2e
 
 If you are at the last word of a line, the "w" command will take you to the
 first word in the next line.  Thus you can use this to move through a
diff --git a/runtime/doc/usr_41.txt b/runtime/doc/usr_41.txt
index da095e13f4..7d4e3a2b09 100644
--- a/runtime/doc/usr_41.txt
+++ b/runtime/doc/usr_41.txt
@@ -1,4 +1,4 @@
-*usr_41.txt*	For Vim version 8.2.  Last change: 2020 Dec 19
+*usr_41.txt*	For Vim version 8.2.  Last change: 2021 Jan 08
 
 		     VIM USER MANUAL - by Bram Moolenaar
 
@@ -122,14 +122,14 @@ starts with a zero.  "017" is decimal 15.  A binary number starts with "0b" or
 decimal number, it will be interpreted as an octal number!
    The ":echo" command always prints decimal numbers.  Example: >
 
-	:echo 0x7f 036
+	:echo 0x7f 0o36
 <	127 30 ~
 
 A number is made negative with a minus sign.  This also works for hexadecimal,
 octal and binary numbers.  A minus sign is also used for subtraction.  Compare
 this with the previous example: >
 
-	:echo 0x7f -036
+	:echo 0x7f -0o36
 <	97 ~
 
 White space in an expression is ignored.  However, it's recommended to use it
@@ -137,7 +137,7 @@ for separating items, to make the expression easier to read.  For example, to
 avoid the confusion with a negative number above, put a space between the
 minus sign and the following number: >
 
-	:echo 0x7f - 036
+	:echo 0x7f - 0o36
 
 ==============================================================================
 *41.2*	Variables
diff --git a/runtime/doc/vim9.txt b/runtime/doc/vim9.txt
index b30db0b869..a7b91db0a4 100644
--- a/runtime/doc/vim9.txt
+++ b/runtime/doc/vim9.txt
@@ -1,4 +1,4 @@
-*vim9.txt*	For Vim version 8.2.  Last change: 2021 Jan 03
+*vim9.txt*	For Vim version 8.2.  Last change: 2021 Jan 10
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -52,8 +52,9 @@ The Vim9 script syntax and semantics are used in:
 - a script file where the first command is `vim9script`
 - an autocommand defined in the context of the above
 
-When using `:function` in a Vim9 script file the legacy syntax is used.
-However, this can be confusing and is therefore discouraged.
+When using `:function` in a Vim9 script file the legacy syntax is used, with
+the highest |scriptversion|.  However, this can be confusing and is therefore
+discouraged.
 
 Vim9 script and legacy Vim script can be mixed.  There is no requirement to
 rewrite old scripts, they keep working as before.  You may want to use a few
@@ -70,28 +71,29 @@ Overview ~
 Brief summary of the differences you will most often encounter when using Vim9
 script and `:def` functions; details are below:
 - Comments start with #, not ": >
-  	echo "hello"   # comment
+	echo "hello"   # comment
 - Using a backslash for line continuation is hardly ever needed: >
-  	echo "hello "
+	echo "hello "
 	     .. yourName
 	     .. ", how are you?"
 - White space is required in many places.
 - Assign values without `:let`, declare variables with `:var`: >
-  	var count = 0
+	var count = 0
 	count += 3
 - Constants can be declared with `:final` and `:const`: >
-  	final matches = []		  # add matches
+	final matches = []		  # add matches
 	const names = ['Betty', 'Peter']  # cannot be changed
 - `:final` cannot be used as an abbreviation of `:finally`.
 - Variables and functions are script-local by default.
 - Functions are declared with argument types and return type: >
 	def CallMe(count: number, message: string): bool
 - Call functions without `:call`: >
-  	writefile(['done'], 'file.txt')
+	writefile(['done'], 'file.txt')
 - You cannot use `:xit`, `:t`, `:append`, `:change`, `:insert` or curly-braces
   names.
 - A range before a command must be prefixed with a colon: >
-  	:%s/this/that
+	:%s/this/that
+- Unless mentioned specifically, the highest |scriptversion| is used.
 
 
 Comments starting with # ~
@@ -315,7 +317,7 @@ The constant only applies to the value itself, not what it refers to. >
 	NAMES[0] = ["Jack"]     # Error!
 	NAMES[0][0] = "Jack"    # Error!
 	NAMES[1] = ["Emma"]     # Error!
-	Names[1][0] = "Emma"    # OK, now females[0] == "Emma"
+	NAMES[1][0] = "Emma"    # OK, now females[0] == "Emma"
 
 <							*E1092*
 Declaring more than one variable at a time, using the unpack notation, is
@@ -432,7 +434,7 @@ possible just before or after the operator.  For example: >
 		   .. middle
 		   .. end
 	var total = start +
-	            end -
+		    end -
 		    correction
 	var result = positive
 			? PosFunc(arg)
@@ -629,9 +631,9 @@ one: >
 
 When using "!" for inverting, there is no error for using any type and the
 result is a boolean.  "!!" can be used to turn any value into boolean: >
-	!'yes'	    		== false
+	!'yes'			== false
 	!![]			== false
-	!![1, 2, 3]    		== true
+	!![1, 2, 3]		== true
 
 When using "`.."` for string concatenation arguments of simple types are
 always converted to string: >
@@ -651,6 +653,14 @@ byte indexes. Example: >
 	echo 'bár'[1]
 In legacy script this results in the character 0xc3 (an illegal byte), in Vim9
 script this results in the string 'á'.
+A negative index is counting from the end, "[-1]" is the last character.
+If the index is out of range then an empty string results.
+
+In legacy script "++var" and "--var" would be silently accepted and have no
+effect.  This is an error in Vim9 script.
+
+Numbers starting with zero are not considered to be octal, only numbers
+starting with "0o" are octal: "0o744". |scriptversion-4|
 
 
 What to watch out for ~
@@ -689,7 +699,7 @@ Vim9 functions are compiled as a whole: >
 	  if !has('feature')
 	    return
 	  endif
-	  use-feature  # May give compilation error
+	  use-feature  # May give a compilation error
 	enddef
 For a workaround, split it in two functions: >
 	func Maybe()
@@ -709,6 +719,25 @@ evaluates to false: >
 	    use-feature
 	  endif
 	enddef
+<							*vim9-user-command*
+Another side effect of compiling a function is that the precense of a user
+command is checked at compile time.  If the user command is defined later an
+error will result.  This works: >
+	command -nargs=1 MyCommand echom <q-args>
+	def Works()
+	  MyCommand 123
+	enddef
+This will give an error for "MyCommand" not being defined: >
+	def Works()
+	  command -nargs=1 MyCommand echom <q-args>
+	  MyCommand 123
+	enddef
+A workaround is to invoke the command indirectly with `:execute`: >
+	def Works()
+	  command -nargs=1 MyCommand echom <q-args>
+	  execute 'MyCommand 123'
+	enddef
+
 Note that for unrecognized commands there is no check for "|" and a following
 command.  This will give an error for missing `endif`: >
 	def Maybe()
@@ -946,6 +975,12 @@ an error, thus breaking backwards compatibility.  For example:
 - Using a string value when setting a number options.
 - Using a number where a string is expected.   *E1024*
 
+One consequence is that the item type of a list or dict given to map() must
+not change.  This will give an error in compiled code: >
+	map([1, 2, 3], (i, v) => 'item ' .. i)
+	E1012: Type mismatch; expected list<number> but got list<string>
+Instead use |mapnew()|.
+
 ==============================================================================
 
 5. Namespace, Import and Export
@@ -1055,14 +1090,14 @@ actually needed.  A recommended mechanism:
 
 1. In the plugin define user commands, functions and/or mappings that refer to
    an autoload script. >
-   	command -nargs=1 SearchForStuff call searchfor#Stuff(<f-args>)
+	command -nargs=1 SearchForStuff call searchfor#Stuff(<f-args>)
 
 <   This goes in .../plugin/anyname.vim.  "anyname.vim" can be freely chosen.
 
 2. In the autoload script do the actual work.  You can import items from
    other files to split up functionality in appropriate pieces. >
 	vim9script
-        import FilterFunc from "../import/someother.vim"
+	import FilterFunc from "../import/someother.vim"
 	def searchfor#Stuff(arg: string)
 	  var filtered = FilterFunc(arg)
 	  ...
diff --git a/runtime/ftplugin/erlang.vim b/runtime/ftplugin/erlang.vim
index ece11d7249..c775247f51 100644
--- a/runtime/ftplugin/erlang.vim
+++ b/runtime/ftplugin/erlang.vim
@@ -1,87 +1,83 @@
 " Vim ftplugin file
-" Language:     Erlang
+" Language:     Erlang (http://www.erlang.org)
+" Maintainer:   Csaba Hoch <csaba.hoch@gmail.com>
 " Author:       Oscar Hellström <oscar@oscarh.net>
 " Contributors: Ricardo Catalinas Jiménez <jimenezrick@gmail.com>
 "               Eduardo Lopez (http://github.com/tapichu)
+"               Arvid Bjurklint (http://github.com/slarwise)
+" Last Update:  2021-Jan-08
 " License:      Vim license
-" Version:      2012/01/25
+" URL:          https://github.com/vim-erlang/vim-erlang-runtime
 
 if exists('b:did_ftplugin')
-	finish
-else
-	let b:did_ftplugin = 1
-endif
-
-if exists('s:did_function_definitions')
-	call s:SetErlangOptions()
-	finish
-else
-	let s:did_function_definitions = 1
+  finish
 endif
+let b:did_ftplugin = 1
 
 let s:cpo_save = &cpo
 set cpo&vim
 
-if !exists('g:erlang_keywordprg')
-	let g:erlang_keywordprg = 'erl -man'
-endif
+let &l:keywordprg = get(g:, 'erlang_keywordprg', 'erl -man')
 
-if !exists('g:erlang_folding')
-	let g:erlang_folding = 0
+if get(g:, 'erlang_folding', 0)
+  setlocal foldmethod=expr
+  setlocal foldexpr=GetErlangFold(v:lnum)
+  setlocal foldtext=ErlangFoldText()
 endif
 
-let s:erlang_fun_begin = '^\a\w*(.*$'
-let s:erlang_fun_end   = '^[^%]*\.\s*\(%.*\)\?$'
-
-function s:SetErlangOptions()
-	if g:erlang_folding
-		setlocal foldmethod=expr
-		setlocal foldexpr=GetErlangFold(v:lnum)
-		setlocal foldtext=ErlangFoldText()
-	endif
+setlocal comments=:%%%,:%%,:%
+setlocal commentstring=%%s
 
-	setlocal comments=:%%%,:%%,:%
-	setlocal commentstring=%%s
+setlocal formatoptions+=ro
 
-	setlocal formatoptions+=ro
-	let &l:keywordprg = g:erlang_keywordprg
-endfunction
+setlocal suffixesadd=.erl,.hrl
 
-function GetErlangFold(lnum)
-	let lnum = a:lnum
-	let line = getline(lnum)
+let &l:include = '^\s*-\%(include\|include_lib\)\s*("\zs\f*\ze")'
+let &l:define  = '^\s*-\%(define\|record\|type\|opaque\)'
 
-	if line =~ s:erlang_fun_end
-		return '<1'
-	endif
+let s:erlang_fun_begin = '^\a\w*(.*$'
+let s:erlang_fun_end   = '^[^%]*\.\s*\(%.*\)\?$'
 
-	if line =~ s:erlang_fun_begin && foldlevel(lnum - 1) == 1
-		return '1'
-	endif
+if !exists('*GetErlangFold')
+  function GetErlangFold(lnum)
+    let lnum = a:lnum
+    let line = getline(lnum)
 
-	if line =~ s:erlang_fun_begin
-		return '>1'
-	endif
+    if line =~ s:erlang_fun_end
+      return '<1'
+    endif
 
-	return '='
-endfunction
+    if line =~ s:erlang_fun_begin && foldlevel(lnum - 1) == 1
+      return '1'
+    endif
 
-function ErlangFoldText()
-	let line    = getline(v:foldstart)
-	let foldlen = v:foldend - v:foldstart + 1
-	let lines   = ' ' . foldlen . ' lines: ' . substitute(line, "[\ \t]*", '', '')
-	if foldlen < 10
-		let lines = ' ' . lines
-	endif
-	let retval = '+' . v:folddashes . lines
+    if line =~ s:erlang_fun_begin
+      return '>1'
+    endif
 
-	return retval
-endfunction
+    return '='
+  endfunction
+endif
 
-call s:SetErlangOptions()
+if !exists('*ErlangFoldText')
+  function ErlangFoldText()
+    let line    = getline(v:foldstart)
+    let foldlen = v:foldend - v:foldstart + 1
+    let lines   = ' ' . foldlen . ' lines: ' . substitute(line, "[\ \t]*", '', '')
+    if foldlen < 10
+      let lines = ' ' . lines
+    endif
+    let retval = '+' . v:folddashes . lines
+
+    return retval
+  endfunction
+endif
 
-let b:undo_ftplugin = "setlocal foldmethod< foldexpr< foldtext<"
-	\ . " comments< commentstring< formatoptions<"
+let b:undo_ftplugin = "setlocal keywordprg< foldmethod< foldexpr< foldtext<"
+      \ . " comments< commentstring< formatoptions< suffixesadd< include<"
+      \ . " define<"
 
 let &cpo = s:cpo_save
 unlet s:cpo_save
+
+" vim: sw=2 et
diff --git a/runtime/ftplugin/fstab.vim b/runtime/ftplugin/fstab.vim
index 3e7