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*repeat.txt*    For Vim version 7.2.  Last change: 2009 Nov 04


                  VIM REFERENCE MANUAL    by Bram Moolenaar


Repeating commands, Vim scripts and debugging                   *repeating*

Chapter 26 of the user manual introduces repeating |usr_26.txt|.

1. Single repeats       |single-repeat|
2. Multiple repeats     |multi-repeat|
3. Complex repeats      |complex-repeat|
4. Using Vim scripts    |using-scripts|
5. Debugging scripts    |debug-scripts|
6. Profiling            |profiling|

==============================================================================
1. Single repeats                                       *single-repeat*

                                                        *.*
.                       Repeat last change, with count replaced with [count].
                        Also repeat a yank command, when the 'y' flag is
                        included in 'cpoptions'.  Does not repeat a
                        command-line command.

Simple changes can be repeated with the "." command.  Without a count, the
count of the last change is used.  If you enter a count, it will replace the
last one.  If the last change included a specification of a numbered register,
the register number will be incremented.  See |redo-register| for an example
how to use this.  Note that when repeating a command that used a Visual
selection, the same SIZE of area is used, see |visual-repeat|.

                                                        *@:*
@:                      Repeat last command-line [count] times.
                        {not available when compiled without the
                        |+cmdline_hist| feature}


==============================================================================
2. Multiple repeats                                     *multi-repeat*

                                                *:g* *:global* *E147* *E148*
:[range]g[lobal]/{pattern}/[cmd]
                        Execute the Ex command [cmd] (default ":p") on the
                        lines within [range] where {pattern} matches.

:[range]g[lobal]!/{pattern}/[cmd]
                        Execute the Ex command [cmd] (default ":p") on the
                        lines within [range] where {pattern} does NOT match.

                                                        *:v* *:vglobal*
:[range]v[global]/{pattern}/[cmd]
                        Same as :g!.

Instead of the '/' which surrounds the {pattern}, you can use any other
single byte character, but not an alphanumeric character, '\', '"' or '|'.
This is useful if you want to include a '/' in the search pattern or
replacement string.

For the definition of a pattern, see |pattern|.

The global commands work by first scanning through the [range] lines and
marking each line where a match occurs (for a multi-line pattern, only the
start of the match matters).
In a second scan the [cmd] is executed for each marked line with its line
number prepended.  For ":v" and ":g!" the command is executed for each not
marked line.  If a line is deleted its mark disappears.
The default for [range] is the whole buffer (1,$).  Use "CTRL-C" to interrupt
the command.  If an error message is given for a line, the command for that
line is aborted and the global command continues with the next marked or
unmarked line.

To repeat a non-Ex command, you can use the ":normal" command: >
        :g/pat/normal {commands}
Make sure that {commands} ends with a whole command, otherwise Vim will wait
for you to type the rest of the command for each match.  The screen will not
have been updated, so you don't know what you are doing.  See |:normal|.

The undo/redo command will undo/redo the whole global command at once.
The previous context mark will only be set once (with "''" you go back to
where the cursor was before the global command).

The global command sets both the last used search pattern and the last used
substitute pattern (this is vi compatible).  This makes it easy to globally
replace a string:
        :g/pat/s//PAT/g
This replaces all occurrences of "pat" with "PAT".  The same can be done with:
        :%s/pat/PAT/g
Which is two characters shorter!

When using "global" in Ex mode, a special case is using ":visual" as a
command.  This will move to a matching line, go to Normal mode to let you
execute commands there until you use |Q| to return to Ex mode.  This will be
repeated for each matching line.  While doing this you cannot use ":global".
To abort this type CTRL-C twice.

==============================================================================
3. Complex repeats                                      *complex-repeat*

                                                        *q* *recording*
q{0-9a-zA-Z"}           Record typed characters into register {0-9a-zA-Z"}
                        (uppercase to append).  The 'q' command is disabled
                        while executing a register, and it doesn't work inside
                        a mapping.  {Vi: no recording}

q                       Stops recording.  (Implementation note: The 'q' that
                        stops recording is not stored in the register, unless
                        it was the result of a mapping)  {Vi: no recording}

                                                        *@*
@{0-9a-z".=*}           Execute the contents of register {0-9a-z".=*} [count]
                        times.  Note that register '%' (name of the current
                        file) and '#' (name of the alternate file) cannot be
                        used.  For "@=" you are prompted to enter an
                        expression.  The result of the expression is then
                        executed.  See also |@:|.  {Vi: only named registers}

                                                        *@@* *E748*
@@                      Repeat the previous @{0-9a-z":*} [count] times.

:[addr]*{0-9a-z".=}                                             *:@* *:star*
:[addr]@{0-9a-z".=*}    Execute the contents of register {0-9a-z".=*} as an Ex
                        command.  First set cursor at line [addr] (default is
                        current line).  When the last line in the register does
                        not have a <CR> it will be added automatically when
                        the 'e' flag is present in 'cpoptions'.
                        Note that the ":*" command is only recognized when the
                        '*' flag is present in 'cpoptions'.  This is NOT the
                        default when 'nocompatible' is used.
                        For ":@=" the last used expression is used.  The
                        result of evaluating the expression is executed as an
                        Ex command.
                        Mappings are not recognized in these commands.
                        {Vi: only in some versions} Future: Will execute the
                        register for each line in the address range.

                                                        *:@:*
:[addr]@:               Repeat last command-line.  First set cursor at line
                        [addr] (default is current line).  {not in Vi}

                                                        *:@@*
:[addr]@@               Repeat the previous :@{0-9a-z"}.  First set cursor at
                        line [addr] (default is current line).  {Vi: only in
                        some versions}

==============================================================================
4. Using Vim scripts                                    *using-scripts*

For writing a Vim script, see chapter 41 of the user manual |usr_41.txt|.

                                        *:so* *:source* *load-vim-script*
:so[urce] {file}        Read Ex commands from {file}.  These are commands that
                        start with a ":".
                        Triggers the |SourcePre| autocommand.

:so[urce]! {file}       Read Vim commands from {file}.  These are commands
                        that are executed from Normal mode, like you type
                        them.
                        When used after |:global|, |:argdo|, |:windo|,
                        |:bufdo|, in a loop or when another command follows
                        the display won't be updated while executing the
                        commands.
                        {not in Vi}

                                                        *:ru* *:runtime*
:ru[ntime][!] {file} ..
                        Read Ex commands from {file} in each directory given
                        by 'runtimepath'.  There is no error for non-existing
                        files.  Example: >
                                :runtime syntax/c.vim

<                       There can be multiple {file} arguments, separated by
                        spaces.  Each {file} is searched for in the first
                        directory from 'runtimepath', then in the second
                        directory, etc.  Use a backslash to include a space
                        inside {file} (although it's better not to use spaces
                        in file names, it causes trouble).

                        When [!] is included, all found files are sourced.
                        When it is not included only the first found file is
                        sourced.

                        When {file} contains wildcards it is expanded to all
                        matching files.  Example: >
                                :runtime! plugin/*.vim
<                       This is what Vim uses to load the plugin files when
                        starting up.  This similar command: >
                                :runtime plugin/*.vim
<                       would source the first file only.

                        When 'verbose' is one or higher, there is a message
                        when no file could be found.
                        When 'verbose' is two or higher, there is a message
                        about each searched file.
                        {not in Vi}

:scripte[ncoding] [encoding]            *:scripte* *:scriptencoding* *E167*
                        Specify the character encoding used in the script.
                        The following lines will be converted from [encoding]
                        to the value of the 'encoding' option, if they are
                        different.  Examples: >
                                scriptencoding iso-8859-5
                                scriptencoding cp932
<
                        When [encoding] is empty, no conversion is done.  This
                        can be used to restrict conversion to a sequence of
                        lines: >
                                scriptencoding euc-jp
                                ... lines to be converted ...
                                scriptencoding
                                ... not converted ...

<                       When conversion isn't supported by the system, there
                        is no error message and no conversion is done.

                        Don't use "ucs-2" or "ucs-4", scripts cannot be in
                        these encodings (they would contain NUL bytes).
                        When a sourced script starts with a BOM (Byte Order
                        Mark) in utf-8 format Vim will recognized it, no need
                        to use ":scriptencoding utf-8" then.

                        When compiled without the |+multi_byte| feature this
                        command is ignored.
                        {not in Vi}

                                                *:scrip* *:scriptnames*
:scrip[tnames]          List all sourced script names, in the order they were
                        first sourced.  The number is used for the script ID
                        |<SID>|.
                        {not in Vi} {not available when compiled without the
                        |+eval| feature}

                                                *:fini* *:finish* *E168*
:fini[sh]               Stop sourcing a script.  Can only be used in a Vim
                        script file.  This is a quick way to skip the rest of
                        the file.  If it is used after a |:try| but before the
                        matching |:finally| (if present), the commands
                        following the ":finally" up to the matching |:endtry|
                        are executed first.  This process applies to all
                        nested ":try"s in the script.  The outermost ":endtry"
                        then stops sourcing the script.  {not in Vi}

All commands and command sequences can be repeated by putting them in a named
register and then executing it.  There are two ways to get the commands in the
register:
- Use the record command "q".  You type the commands once, and while they are
  being executed they are stored in a register.  Easy, because you can see
  what you are doing.  If you make a mistake, "p"ut the register into the
  file, edit the command sequence, and then delete it into the register
  again.  You can continue recording by appending to the register (use an
  uppercase letter).
- Delete or yank the command sequence into the register.

Often used command sequences can be put under a function key with the ':map'
command.

An alternative is to put the commands in a file, and execute them with the
':source!' command.  Useful for long command sequences.  Can be combined with
the ':map' command to put complicated commands under a function key.

The ':source' command reads Ex commands from a file line by line.  You will
have to type any needed keyboard input.  The ':source!' command reads from a
script file character by character, interpreting each character as if you
typed it.

Example: When you give the ":!ls" command you get the |hit-enter| prompt.  If
you ':source' a file with the line "!ls" in it, you will have to type the
<Enter> yourself.  But if you ':source!' a file with the line ":!ls" in it,
the next characters from that file are read until a <CR> is found.  You will
not have to type <CR> yourself, unless ":!ls" was the last line in the file.

It is possible to put ':source[!]' commands in the script file, so you can
make a top-down hierarchy of script files.  The ':source' command can be
nested as deep as the number of files that can be opened at one time (about
15).  The ':source!' command can be nested up to 15 levels deep.

You can use the "<sfile>" string (literally, this is not a special key) inside
of the sourced file, in places where a file name is expected.  It will be
replaced by the file name of the sourced file.  For example, if you have a
"other.vimrc" file in the same directory as your ".vimrc" file, you can source
it from your ".vimrc" file with this command: >
        :source <sfile>:h/other.vimrc

In script files terminal-dependent key codes are represented by
terminal-independent two character codes.  This means that they can be used
in the same way on different kinds of terminals.  The first character of a
key code is 0x80 or 128, shown on the screen as "~@".  The second one can be
found in the list |key-notation|.  Any of these codes can also be entered
with CTRL-V followed by the three digit decimal code.  This does NOT work for
the <t_xx> termcap codes, these can only be used in mappings.

                                                        *:source_crnl* *W15*
MS-DOS, Win32 and OS/2: Files that are read with ":source" normally have
<CR><NL> <EOL>s.  These always work.  If you are using a file with <NL> <EOL>s
(for example, a file made on Unix), this will be recognized if 'fileformats'
is not empty and the first line does not end in a <CR>.  This fails if the
first line has something like ":map <F1> :help^M", where "^M" is a <CR>.  If
the first line ends in a <CR>, but following ones don't, you will get an error
message, because the <CR> from the first lines will be lost.

Mac Classic: Files that are read with ":source" normally have <CR> <EOL>s.
These always work.  If you are using a file with <NL> <EOL>s (for example, a
file made on Unix), this will be recognized if 'fileformats' is not empty and
the first line does not end in a <CR>.  Be careful not to use a file with <NL>
linebreaks which has a <CR> in first line.

On other systems, Vim expects ":source"ed files to end in a <NL>.  These
always work.  If you are using a file with <CR><NL> <EOL>s (for example, a
file made on MS-DOS), all lines will have a trailing <CR>.  This may cause
problems for some commands (e.g., mappings).  There is no automatic <EOL>
detection, because it's common to start with a line that defines a mapping
that ends in a <CR>, which will confuse the automaton.

                                                        *line-continuation*
Long lines in a ":source"d Ex command script file can be split by inserting
a line continuation symbol "\" (backslash) at the start of the next line.
There can be white space before the backslash, which is ignored.

Example: the lines >
        :set comments=sr:/*,mb:*,el:*/,
                     \://,
                     \b:#,
                     \:%,
                     \n:>,
                     \fb:-
are interpreted as if they were given in one line:
        :set comments=sr:/*,mb:*,el:*/,://,b:#,:%,n:>,fb:-

All leading whitespace characters in the line before a backslash are ignored.
Note however that trailing whitespace in the line before it cannot be
inserted freely; it depends on the position where a command is split up
whether additional whitespace is allowed or not.

When a space is required it's best to put it right after the backslash.  A
space at the end of a line is hard to see and may be accidentally deleted. >
        :syn match Comment
                \ "very long regexp"
                \ keepend

There is a problem with the ":append" and ":insert" commands: >
   :1append
   \asdf
   .
The backslash is seen as a line-continuation symbol, thus this results in the
command: >
   :1appendasdf
   .
To avoid this, add the 'C' flag to the 'cpoptions' option: >
   :set cpo+=C
   :1append
   \asdf
   .
   :set cpo-=C

Note that when the commands are inside a function, you need to add the 'C'
flag when defining the function, it is not relevant when executing it. >
   :set cpo+=C
   :function Foo()
   :1append
   \asdf
   .
   :endfunction
   :set cpo-=C

Rationale:
        Most programs work with a trailing backslash to indicate line
        continuation.  Using this in Vim would cause incompatibility with Vi.
        For example for this Vi mapping: >
                :map xx  asdf\
<       Therefore the unusual leading backslash is used.

==============================================================================
5. Debugging scripts                                    *debug-scripts*

Besides the obvious messages that you can add to your scripts to find out what
they are doing, Vim offers a debug mode.  This allows you to step through a
sourced file or user function and set breakpoints.

NOTE: The debugging mode is far from perfect.  Debugging will have side
effects on how Vim works.  You cannot use it to debug everything.  For
example, the display is messed up by the debugging messages.
{Vi does not have a debug mode}

An alternative to debug mode is setting the 'verbose' option.  With a bigger
number it will give more verbose messages about what Vim is doing.


STARTING DEBUG MODE                                             *debug-mode*

To enter debugging mode use one of these methods:
1. Start Vim with the |-D| argument: >
        vim -D file.txt
<  Debugging will start as soon as the first vimrc file is sourced.  This is
   useful to find out what is happening when Vim is starting up.  A side
   effect is that Vim will switch the terminal mode before initialisations
   have finished, with unpredictable results.
   For a GUI-only version (Windows, Macintosh) the debugging will start as
   soon as the GUI window has been opened.  To make this happen early, add a
   ":gui" command in the vimrc file.
                                                                *:debug*
2. Run a command with ":debug" prepended.  Debugging will only be done while
   this command executes.  Useful for debugging a specific script or user
   function.  And for scripts and functions used by autocommands.  Example: >
        :debug edit test.txt.gz

3. Set a breakpoint in a sourced file or user function.  You could do this in
   the command line: >
        vim -c "breakadd file */explorer.vim" .
<  This will run Vim and stop in the first line of the "explorer.vim" script.
   Breakpoints can also be set while in debugging mode.

In debugging mode every executed command is displayed before it is executed.
Comment lines, empty lines and lines that are not executed are skipped.  When
a line contains two commands, separated by "|", each command will be displayed
separately.


DEBUG MODE

Once in debugging mode, the usual Ex commands can be used.  For example, to
inspect the value of a variable: >
        echo idx
When inside a user function, this will print the value of the local variable
"idx".  Prepend "g:" to get the value of a global variable: >
        echo g:idx
All commands are executed in the context of the current function or script.
You can also set options, for example setting or resetting 'verbose' will show
what happens, but you might want to set it just before executing the lines you
are interested in: >
        :set verbose=20

Commands that require updating the screen should be avoided, because their
effect won't be noticed until after leaving debug mode.  For example: >
        :help
won't be very helpful.

There is a separate command-line history for debug mode.

The line number for a function line is relative to the start of the function.
If you have trouble figuring out where you are, edit the file that defines
the function in another Vim, search for the start of the function and do
"99j".  Replace "99" with the line number.

Additionally, these commands can be used:
                                                        *>cont*
        cont            Continue execution until the next breakpoint is hit.
                                                        *>quit*
        quit            Abort execution.  This is like using CTRL-C, some
                        things might still be executed, doesn't abort
                        everything.  Still stops at the next breakpoint.
                                                        *>next*
        next            Execute the command and come back to debug mode when
                        it's finished.  This steps over user function calls
                        and sourced files.
                                                        *>step*
        step            Execute the command and come back to debug mode for
                        the next command.  This steps into called user
                        functions and sourced files.
                                                        *>interrupt*
        interrupt       This is like using CTRL-C, but unlike ">quit" comes
                        back to debug mode for the next command that is
                        executed.  Useful for testing |:finally| and |:catch|
                        on interrupt exceptions.
                                                        *>finish*
        finish          Finish the current script or user function and come
                        back to debug mode for the command after the one that
                        sourced or called it.

About the additional commands in debug mode:
- There is no command-line completion for them, you get the completion for the
  normal Ex commands only.
- You can shorten them, up to a single character: "c", "n", "s" and "f".
- Hitting <CR> will repeat the previous one.  When doing another command, this
  is reset (because it's not clear what you want to repeat).
- When you want to use the Ex command with the same name, prepend a colon:
  ":cont", ":next", ":finish" (or shorter).


DEFINING BREAKPOINTS
                                                        *:breaka* *:breakadd*
:breaka[dd] func [lnum] {name}
                Set a breakpoint in a function.  Example: >
                        :breakadd func Explore
<               Doesn't check for a valid function name, thus the breakpoint
                can be set before the function is defined.

:breaka[dd] file [lnum] {name}
                Set a breakpoint in a sourced file.  Example: >
                        :breakadd file 43 .vimrc

:breaka[dd] here
                Set a breakpoint in the current line of the current file.
                Like doing: >
                        :breakadd file <cursor-line> <current-file>
<               Note that this only works for commands that are executed when
                sourcing the file, not for a function defined in that file.

The [lnum] is the line number of the breakpoint.  Vim will stop at or after
this line.  When omitted line 1 is used.

                                                        *:debug-name*
{name} is a pattern that is matched with the file or function name.  The
pattern is like what is used for autocommands.  There must be a full match (as
if the pattern starts with "^" and ends in "$").  A "*" matches any sequence
of characters.  'ignorecase' is not used, but "\c" can be used in the pattern
to ignore case |/\c|.  Don't include the () for the function name!

The match for sourced scripts is done against the full file name.  If no path
is specified the current directory is used.  Examples: >
        breakadd file explorer.vim
matches "explorer.vim" in the current directory. >
        breakadd file *explorer.vim
matches ".../plugin/explorer.vim", ".../plugin/iexplorer.vim", etc. >
        breakadd file */explorer.vim
matches ".../plugin/explorer.vim" and "explorer.vim" in any other directory.

The match for functions is done against the name as it's shown in the output
of ":function".  For local functions this means that something like "<SNR>99_"
is prepended.

Note that functions are first loaded and later executed.  When they are loaded
the "file" breakpoints are checked, when they are executed the "func"
breakpoints.


DELETING BREAKPOINTS
                                                *:breakd* *:breakdel* *E161*
:breakd[el] {nr}
                Delete breakpoint {nr}.  Use |:breaklist| to see the number of
                each breakpoint.

:breakd[el] *
                Delete all breakpoints.

:breakd[el] func [lnum] {name}
                Delete a breakpoint in a function.

:breakd[el] file [lnum] {name}
                Delete a breakpoint in a sourced file.

:breakd[el] here
                Delete a breakpoint at the current line of the current file.

When [lnum] is omitted, the first breakpoint in the function or file is
deleted.
The {name} must be exactly the same as what was typed for the ":breakadd"
command.  "explorer", "*explorer.vim" and "*explorer*" are different.


LISTING BREAKPOINTS
                                                        *:breakl* *:breaklist*
:breakl[ist]
                List all breakpoints.


OBSCURE

                                                *:debugg* *:debuggreedy*
:debugg[reedy]
                Read debug mode commands from the normal input stream, instead
                of getting them directly from the user.  Only useful for test
                scripts.  Example: >
                  echo 'q^Mq' | vim -e -s -c debuggreedy -c 'breakadd file script.vim' -S script.vim

:0debugg[reedy]
                Undo ":debuggreedy": get debug mode commands directly from the
                user, don't use typeahead for debug commands.

==============================================================================
6. Profiling                                            *profile* *profiling*

Profiling means that Vim measures the time that is spend on executing
functions and/or scripts.  The |+profile| feature is required for this.
It is only included when Vim was compiled with "huge" features.
{Vi does not have profiling}

You can also use the |reltime()| function to measure time.  This only requires
the |+reltime| feature, which is present more often.

:prof[ile] start {fname}                        *:prof* *:profile* *E750*
                Start profiling, write the output in {fname} upon exit.
                If {fname} already exists it will be silently overwritten.
                The variable |v:profiling| is set to one.

:prof[ile] pause
                Don't profile until the following ":profile continue".  Can be
                used when doing something that should not be counted (e.g., an
                external command).  Does not nest.

:prof[ile] continue
                Continue profiling after ":profile pause".

:prof[ile] func {pattern}
                Profile function that matches the pattern {pattern}.
                See |:debug-name| for how {pattern} is used.

:prof[ile][!] file {pattern}
                Profile script file that matches the pattern {pattern}.
                See |:debug-name| for how {pattern} is used.
                This only profiles the script itself, not the functions
                defined in it.
                When the [!] is added then all functions defined in the script
                will also be profiled.  But only if the script is loaded after
                this command.


:profd[el] ...                                          *:profd* *:profdel*
                Stop profiling for the arguments specified. See |:breakdel|
                for the arguments.


You must always start with a ":profile start fname" command.  The resulting
file is written when Vim exits.  Here is an example of the output, with line
numbers prepended for the explanation:

  1 FUNCTION  Test2() ~
  2 Called 1 time ~
  3 Total time:   0.155251 ~
  4  Self time:   0.002006 ~
  5  ~
  6 count  total (s)   self (s) ~
  7     9              0.000096   for i in range(8) ~
  8     8   0.153655   0.000410     call Test3() ~
  9     8              0.000070   endfor ~
 10                               " Ask a question ~
 11     1              0.001341   echo input("give me an answer: ") ~

The header (lines 1-4) gives the time for the whole function.  The "Total"
time is the time passed while the function was executing.  The "Self" time is
the "Total" time reduced by time spent in:
- other user defined functions
- sourced scripts
- executed autocommands
- external (shell) commands

Lines 7-11 show the time spent in each executed line.  Lines that are not
executed do not count.  Thus a comment line is never counted.

The Count column shows how many times a line was executed.  Note that the
"for" command in line 7 is executed one more time as the following lines.
That is because the line is also executed to detect the end of the loop.

The time Vim spends waiting for user input isn't counted at all.  Thus how
long you take to respond to the input() prompt is irrelevant.

Profiling should give a good indication of where time is spent, but keep in
mind there are various things that may clobber the results:

- The accuracy of the time measured depends on the gettimeofday() system
  function.  It may only be as accurate as 1/100 second, even though the times
  are displayed in micro seconds.

- Real elapsed time is measured, if other processes are busy they may cause
  delays at unpredictable moments.  You may want to run the profiling several
  times and use the lowest results.

- If you have several commands in one line you only get one time.  Split the
  line to see the time for the individual commands.

- The time of the lines added up is mostly less than the time of the whole
  function.  There is some overhead in between.

- Functions that are deleted before Vim exits will not produce profiling
  information.  You can check the |v:profiling| variable if needed: >
        :if !v:profiling
        :   delfunc MyFunc
        :endif
<
- Profiling may give weird results on multi-processor systems, when sleep
  mode kicks in or the processor frequency is reduced to save power.

- The "self" time is wrong when a function is used recursively.


 vim:tw=78:ts=8:ft=help:norl: