# Vim documentation: change

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    *change.txt*    For Vim version 6.3.  Last change: 2004 May 08

    		  VIM REFERENCE MANUAL    by Bram Moolenaar

    This file describes commands that delete or change text.  In this context,
    changing text means deleting the text and replacing it with other text using
    one command.  You can undo all of these commands.  You can repeat the non-Ex
    commands with the "." command.

    1. Deleting text		|deleting|
    2. Delete and insert		|delete-insert|

    3. Simple changes		|simple-change|		*changing*
    4. Complex changes		|complex-change|
    5. Copying and moving text	|copy-move|
    6. Formatting text		|formatting|

    For inserting text see |insert.txt|.

    ==============================================================================

    1. Deleting text					*deleting* *E470*

    ["x]<Del>	or					*<Del>* *x* *dl*
    ["x]x			Delete [count] characters under and after the cursor
    			[into register x] (not |linewise|).  Does the same as
    			"dl".
    			The <Del> key does not take a [count].  Instead, it
    			deletes the last character of the count.
    			See |:fixdel| if the <Del> key does not do what you
    			want.  See |'whichwrap'| for deleting a line break
    			(join lines).  {Vi does not support <Del>}

    							*X* *dh*
    ["x]X			Delete [count] characters before the cursor [into
    			register x] (not |linewise|).  Does the same as "dh".
    			Also see |'whichwrap'|.

    							*d*
    ["x]d{motion}		Delete text that {motion} moves over [into register
    			x].  See below for exceptions.

    							*dd*
    ["x]dd			Delete [count] lines [into register x] |linewise|.

    							*D*
    ["x]D			Delete the characters under the cursor until the end
    			of the line and [count]-1 more lines [into register
    			x]; synonym for "d$".
    			(not |linewise|)

    {Visual}["x]x	or					*v_x* *v_d* *v_<Del>*
    {Visual}["x]d   or
    {Visual}["x]<Del>	Delete the highlighted text [into register x] (for
    			{Visual} see |Visual-mode|).  {not in Vi}

    {Visual}["x]CTRL-H   or					*v_CTRL-H* *v_<BS>*
    {Visual}["x]<BS>	When in Select mode: Delete the highlighted text [into
    			register x].

    {Visual}["x]X	or					*v_X* *v_D* *v_b_D*
    {Visual}["x]D		Delete the highlighted lines [into register x] (for
    			{Visual} see |Visual-mode|).  In Visual block mode,
    			"D" deletes the highlighted text plus all text until
    			the end of the line.  {not in Vi}

    						*:d* *:de* *:del* *:delete*
    :[range]d[elete] [x]	Delete [range] lines (default: current line) [into
    			register x].

    :[range]d[elete] [x] {count}
    			Delete {count} lines, starting with [range]
    			(default: current line |cmdline-ranges|) [into
    			register x].

    These commands delete text.  You can repeat them with the "." command
    (except ":d") and undo them.  Use Visual mode to delete blocks of text.  See
    |registers| for an explanation of registers.

    An exception for the d{motion} command: If the motion is not linewise, the
    start and end of the motion are not in the same line, and there are only
    blanks before the start and after the end of the motion, the delete becomes
    linewise.  This means that the delete also removes the line of blanks that you
    might expect to remain.

    Trying to delete an empty region of text (e.g., "d0" in the first column)
    is an error when 'cpoptions' includes the 'E' flag.

    							*J*
    J			Join [count] lines, with a minimum of two lines.
    			Remove the indent and insert up to two spaces (see
    			below).

    							*v_J*
    {Visual}J		Join the highlighted lines, with a minimum of two
    			lines.  Remove the indent and insert up to two spaces
    			(see below).  {not in Vi}

    							*gJ*
    gJ			Join [count] lines, with a minimum of two lines.
    			Don't insert or remove any spaces.  {not in Vi}

    							*v_gJ*
    {Visual}gJ		Join the highlighted lines, with a minimum of two
    			lines.  Don't insert or remove any spaces.  {not in
    			Vi}

    							*:j* *:join*
    :[range]j[oin][!]	Join [range] lines.  Same as "J", except with [!]
    			the join does not insert or delete any spaces.
    			If a [range] has equal start and end values, this
    			command does nothing.  The default behavior is to
    			join the current line with the line below it.
    			{not in Vi: !}

    :[range]j[oin][!] {count}
    			Join {count} lines, starting with [range] (default:
    			current line |cmdline-ranges|).  Same as "J", except
    			with [!] the join does not insert or delete any
    			spaces.
    			{not in Vi: !}

    These commands delete the <EOL> between lines.  This has the effect of joining
    multiple lines into one line.  You can repeat these commands (except ":j") and
    undo them.

    These commands, except "gJ", insert one space in place of the <EOL> unless
    there is trailing white space or the next line starts with a ')'.  These
    commands, except "gJ", delete any leading white space on the next line.  If
    the 'joinspaces' option is on, these commands insert two spaces after a '.',
    '!' or '?' (but if 'cpoptions' includes the 'j' flag, they insert two spaces
    only after a '.').
    The 'B' and 'M' flags in 'formatoptions' change the behavior for inserting
    spaces before and after a multi-byte character |fo-table|.

    ==============================================================================

    2. Delete and insert				*delete-insert* *replacing*

    							*R*
    R			Enter Replace mode: Each character you type replaces
    			an existing character, starting with the character
    			under the cursor.  Repeat the entered text [count]-1
    			times.  See |Replace-mode| for more details.

    							*gR*
    gR			Enter Virtual Replace mode: Each character you type
    			replaces existing characters in screen space.  So a
    			<Tab> may replace several characters at once.
    			Repeat the entered text [count]-1 times.  See
    			|Virtual-Replace-mode| for more details.
    			{not available when compiled without the +vreplace
    			feature}

    							*c*
    ["x]c{motion}		Delete {motion} text [into register x] and start
    			insert.  When  'cpoptions' includes the 'E' flag and
    			there is no text to delete (e.g., with "cTx" when the
    			cursor is just after an 'x'), an error occurs and
    			insert mode does not start (this is Vi compatible).
    			When  'cpoptions' does not include the 'E' flag, the
    			"c" command always starts insert mode, even if there
    			is no text to delete.

    							*cc*
    ["x]cc			Delete [count] lines [into register x] and start
    			insert |linewise|.  If 'autoindent' is on, preserve
    			the indent of the first line.

    							*C*
    ["x]C			Delete from the cursor position to the end of the
    			line and [count]-1 more lines [into register x], and
    			start insert.  Synonym for c$ (not |linewise|).

    							*s*
    ["x]s			Delete [count] characters [into register x] and start
    			insert (s stands for Substitute).  Synonym for "cl"
    			(not |linewise|).

    							*S*
    ["x]S			Delete [count] lines [into register x] and start
    			insert.  Synonym for "cc" |linewise|.

    {Visual}["x]c	or					*v_c* *v_s*
    {Visual}["x]s		Delete the highlighted text [into register x] and
    			start insert (for {Visual} see |Visual-mode|).  {not
    			in Vi}

    							*v_r*
    {Visual}["x]r{char}	Replace all selected characters by {char}.

    							*v_C*
    {Visual}["x]C		Delete the highlighted lines [into register x] and
    			start insert.  In Visual block mode it works
    			differently |v_b_C|.  {not in Vi}

    							*v_S*
    {Visual}["x]S		Delete the highlighted lines [into register x] and
    			start insert (for {Visual} see |Visual-mode|).  {not
    			in Vi}

    							*v_R*
    {Visual}["x]R		Currently just like {Visual}["x]S.  In a next version
    			it might work differently. {not in Vi}

    Notes:
    - You can end Insert and Replace mode with <Esc>.
    - See the section "Insert and Replace mode" |mode-ins-repl| for the other
      special characters in these modes.
    - The effect of [count] takes place after Vim exits Insert or Replace mode.
    - When the 'cpoptions' option contains '$' and the change is within one line,
      Vim continues to show the text to be deleted and puts a '$' at the last
      deleted character.

    See |registers| for an explanation of registers.

    Replace mode is just like Insert mode, except that every character you enter
    deletes one character.  If you reach the end of a line, Vim appends any
    further characters (just like Insert mode).  In Replace mode, the backspace
    key restores the original text (if there was any).  (See section "Insert and
    Replace mode" |mode-ins-repl|).

    						*cw* *cW*
    Special case: "cw" and "cW" work the same as "ce" and "cE" if the cursor is
    on a non-blank.  This is because Vim interprets "cw" as change-word, and a
    word does not include the following white space.  {Vi: "cw" when on a blank
    followed by other blanks changes only the first blank; this is probably a
    bug, because "dw" deletes all the blanks; use the 'w' flag in 'cpoptions' to
    make it work like Vi anyway}

    If you prefer "cw" to include the space after a word, use this mapping:
    	:map cw dwi

    							*:c* *:ch* *:change*
    :{range}c[hange]	Replace lines of text with some different text.
    			Type a line containing only "." to stop replacing.
    			Without {range}, this command changes only the current
    			line.

    ==============================================================================

    3. Simple changes					*simple-change*

    							*r*
    r{char}			Replace the character under the cursor with {char}.
    			If {char} is a <CR> or <NL>, a line break replaces the
    			character.  To replace with a real <CR>, use CTRL-V
    			<CR>.  CTRL-V <NL> replaces with a <Nul>.
    			{Vi: CTRL-V <CR> still replaces with a line break,
    			cannot replace something with a <CR>}
    			If you give a [count], Vim replaces [count] characters
    			with [count] {char}s.  When {char} is a <CR> or <NL>,
    			however, Vim inserts only one <CR>: "5r<CR>" replaces
    			five characters with a single line break.
    			When {char} is a <CR> or <NL>, Vim performs
    			autoindenting.  This works just like deleting the
    			characters that are replaced and then doing
    			"i<CR><Esc>".
    			{char} can be entered as a digraph |digraph-arg|.
    			|:lmap| mappings apply to {char}.  The CTRL-^ command
    			in Insert mode can be used to switch this on/off
    			|i_CTRL-^|.  See |utf-8-char-arg| about using
    			composing characters when 'encoding' is Unicode.

    							*gr*
    gr{char}		Replace the virtual characters under the cursor with
    			{char}.  This replaces in screen space, not file
    			space.  See |gR| and |Virtual-Replace-mode| for more
    			details.  As with |r| a count may be given.
    			{char} can be entered like with |r|.
    			{not available when compiled without the +vreplace
    			feature}

    						*digraph-arg*
    The argument for Normal mode commands like |r| and |t| is a single character.
    When 'cpo' doesn't contain the 'D' flag, this character can also be entered
    like |digraphs|.  First type CTRL-K and then the two digraph characters.
    {not available when compiled without the |+digraphs| feature}

    						*case*
    The following commands change the case of letters.  The currently active
    |locale| is used.  See |:language|.  The LC_CTYPE value matters here.

    							*~*
    ~			'notildeop' option: Switch case of the character
    			under the cursor and move the cursor to the right.
    			If a [count] is given, do that many characters. {Vi:
    			no count}

    ~{motion}		'tildeop' option: switch case of {motion} text. {Vi:
    			tilde cannot be used as an operator}

    							*g~*
    g~{motion}		Switch case of {motion} text. {not in Vi}

    g~g~							*g~g~* *g~~*
    g~~			Switch case of current line. {not in Vi}.

    							*v_~*
    {Visual}~		Switch case of highlighted text (for {Visual} see
    			|Visual-mode|). {not in Vi}

    							*v_U*
    {Visual}U		Make highlighted text uppercase (for {Visual} see
    			|Visual-mode|). {not in Vi}

    							*gU* *uppercase*
    gU{motion}		Make {motion} text uppercase. {not in Vi}
    			Example:
    				:map! <C-F> <Esc>gUiw`]a
     			This works in Insert mode: press CTRL-F to make the
    			word before the cursor uppercase.  Handy to type
    			words in lowercase and then make them uppercase.

    gUgU							*gUgU* *gUU*
    gUU			Make current line uppercase. {not in Vi}.

    							*v_u*
    {Visual}u		Make highlighted text lowercase (for {Visual} see
    			|Visual-mode|).  {not in Vi}

    							*gu* *lowercase*
    gu{motion}		Make {motion} text lowercase. {not in Vi}

    gugu							*gugu* *guu*
    guu			Make current line lowercase. {not in Vi}.

    							*g?* *rot13*
    g?{motion}		Rot13 encode {motion} text. {not in Vi}

    							*v_g?*
    {Visual}g?		Rot13 encode the highlighted text (for {Visual} see
    			|Visual-mode|).  {not in Vi}

    g?g?							*g?g?* *g??*
    g??			Rot13 encode current line. {not in Vi}.

    Adding and subtracting

    							*CTRL-A*
    CTRL-A			Add [count] to the number or alphabetic character at
    			or after the cursor.  {not in Vi}

    							*CTRL-X*
    CTRL-X			Subtract [count] from the number or alphabetic
    			character at or after the cursor.  {not in Vi}

    The CTRL-A and CTRL-X commands work for (signed) decimal numbers, unsigned
    octal and hexadecimal numbers and alphabetic characters.  This depends on the
    'nrformats' option.
    - When 'nrformats' includes "alpha", Vim will change the alphabetic character
      under or after the cursor.  This is useful to make lists with an alphabetic
      index.
    - When 'nrformats' includes "hex", Vim assumes numbers starting with '0x' or
      '0X' are hexadecimal.  The case of the rightmost letter in the number
      determines the case of the resulting hexadecimal number.  If there is no
      letter in the current number, Vim uses the previously detected case.
    - When 'nrformats' includes "octal", Vim considers numbers starting with a '0'
      to be octal.  Other numbers are decimal and may have a preceding minus sign.
      If the cursor is on a number, the commands apply to that number; otherwise
      Vim uses the number to the right of the cursor.

    For numbers with leading zeros (including all octal and hexadecimal numbers),
    Vim preserves the number of characters in the number when possible.  CTRL-A on
    "0077" results in "0100", CTRL-X on "0x100" results in "0x0ff".  Note that
    when 'nrformats' includes "octal", decimal numbers with leading zeros are
    impossible because they are indistinguishable from octal numbers.

    The CTRL-A command is very useful in a macro.  Example: Use the following
    steps to make a numbered list.

    1. Create the first list entry, make sure it starts with a number.
    2. qa	     - start recording into buffer 'a'
    3. Y	     - yank the entry
    4. p	     - put a copy of the entry below the first one
    5. CTRL-A    - increment the number
    6. q	     - stop recording
    7. <count>@a - repeat the yank, put and increment <count> times

    SHIFTING LINES LEFT OR RIGHT				*shift-left-right*

    							*<*
    <{motion}		Shift {motion} lines one 'shiftwidth' leftwards.

    							*<<*
    <<			Shift [count] lines one 'shiftwidth' leftwards.

    							*v_<*
    {Visual}[count]<	Shift the highlighted lines [count] 'shiftwidth'
    			leftwards (for {Visual} see |Visual-mode|).  {not in
    			Vi}

    							*>*
     >{motion}		Shift {motion} lines one 'shiftwidth' rightwards.

    							*>>*
     >>			Shift [count] lines one 'shiftwidth' rightwards.

    							*v_>*
    {Visual}[count]>	Shift the highlighted lines [count] 'shiftwidth'
    			rightwards (for {Visual} see |Visual-mode|).  {not in
    			Vi}

    							*:<*
    :[range]<		Shift [range] lines one 'shiftwidth' left.  Repeat '<'
    			for shifting multiple 'shiftwidth's.

    :[range]< {count}	Shift {count} lines one 'shiftwidth' left, starting
    			with [range] (default current line |cmdline-ranges|).
    			Repeat '<' for shifting multiple 'shiftwidth's.

    :[range]le[ft] [indent]	left align lines in [range].  Sets the indent in the
    			lines to [indent] (default 0).  {not in Vi}

    							*:>*
    :[range]>		Shift {count} [range] lines one 'shiftwidth' right.
    			Repeat '>' for shifting multiple 'shiftwidth's.

    :[range]> {count}	Shift {count} lines one 'shiftwidth' right, starting
    			with [range] (default current line |cmdline-ranges|).
    			Repeat '>' for shifting multiple 'shiftwidth's.

    The ">" and "<" commands are handy for changing the indentation within
    programs.  Use the 'shiftwidth' option to set the size of the white space
    which these commands insert or delete.  Normally the 'shiftwidth' option is 8,
    but you can set it to, say, 3 to make smaller indents.  The shift leftwards
    stops when there is no indent.  The shift right does not affect empty lines.

    If the 'shiftround' option is on, the indent is rounded to a multiple of
    'shiftwidth'.

    If the 'smartindent' option is on, or 'cindent' is on and 'cinkeys' contains
    '#', shift right does not affect lines starting with '#' (these are supposed
    to be C preprocessor lines that must stay in column 1).

    When the 'expandtab' option is off (this is the default) Vim uses <Tab>s as
    much as possible to make the indent.  You can use ">><<" to replace an indent
    made out of spaces with the same indent made out of <Tab>s (and a few spaces
    if necessary).  If the 'expandtab' option is on, Vim uses only spaces.  Then
    you can use ">><<" to replace <Tab>s in the indent by spaces (or use
    ":retab!").

    To move a line several 'shiftwidth's, use Visual mode or the ":" commands.
    For example:
    	Vjj4>		move three lines 4 indents to the right
    	:<<<		move current line 3 indents to the left
    	:>> 5		move 5 lines 2 indents to the right
    	:5>>		move line 5 2 indents to the right

    ==============================================================================

    4. Complex changes					*complex-change*

    							*!* *filter*
    !{motion}{filter}	Filter {motion} text lines through the external
    			program {filter}.

    							*!!*
    !!{filter}		Filter [count] lines through the external program
    			{filter}.

    							*v_!*
    {Visual}!{filter}	Filter the highlighted lines through the external
    			program {filter} (for {Visual} see |Visual-mode|).
    			{not in Vi}

    :{range}![!]{filter} [!][arg]				*:range!*
    			Filter {range} lines through the external program
    			{filter}.  Vim replaces the optional bangs with the
    			latest given command and appends the optional [arg].
    			Vim saves the output of the filter command in a
    			temporary file and then reads the file into the
    			buffer.  Vim uses the 'shellredir' option to redirect
    			the filter output to the temporary file.
    			When the 'R' flag is included in 'cpoptions' marks in
    			the filtered lines are deleted, unless the
    			|:keepmarks| command is used.  Example:
    				:keepmarks '<,'>!sort
     			When the number of lines after filtering is less than
    			before, marks in the missing lines are deleted anyway.

    							*=*
    ={motion}		Filter {motion} lines through the external program
    			given with the 'equalprg' option.  When the 'equalprg'
    			option is empty (this is the default), use the
    			internal formatting function |C-indenting|.  But when
    			'indentexpr' is not empty, it will be used instead
    			|indent-expression|.

    							*==*
    ==			Filter [count] lines like with ={motion}.

    							*v_=*
    {Visual}=		Filter the highlighted lines like with ={motion}.
    			{not in Vi}

    A filter is a program that accepts text at standard input, changes it in some
    way, and sends it to standard output.  You can use the commands above to send
    some text through a filter.  Examples of filters are "sort", which sorts lines
    alphabetically, and "indent", which formats C program files (you need a
    version of indent that works like a filter; not all versions do).  The 'shell'
    option specifies the shell Vim uses to execute the filter command (See also
    the 'shelltype' option).  You can repeat filter commands with ".".  Vim does
    not recognize a comment (starting with '"'') after the ":!" command.

    						*:s* *:su* *:substitute*
    :[range]s[ubstitute]/{pattern}/{string}/[&][c][e][g][p][r][i][I] [count]
    			For each line in [range] replace a match of {pattern}
    			with {string}.
    			For the {pattern} see |pattern|.
    			{string} can be a literal string, or something
    			special; see |sub-replace-special|.
    			When [range] and [count] are omitted, replace in the
    			current line only.
    			When [count] is given, replace in [count] lines,
    			starting with the last line in [range].  When [range]
    			is omitted start in the current line.
    			Also see |cmdline-ranges|.
    			See |:s_flags| for the flags.

    :[range]s[ubstitute] [c][e][g][p][r][i][I] [count]

    :[range]&[&][c][e][g][p][r][i][I] [count]			*:&*
    			Repeat last :substitute with same search pattern and
    			substitute string, but without the same flags.  You
    			may add extra flags (see |:s_flags|).
    			Note that after ":substitute" the '&' flag can't be
    			used, it's recognized as a pattern separator.
    			The space between ":substitute" and the 'c', 'g' and
    			'r' flags isn't required, but in scripts it's a good
    			idea to keep it to avoid confusion.

    :[range]~[&][c][e][g][p][r][i][I] [count]			*:~*
    			Repeat last substitute with same substitute string
    			but with last used search pattern.  This is like
    			":&r".  See |:s_flags| for the flags.

    						*&*
    &			Synonym for ":s//~/" (repeat last substitute).  Note
    			that the flags are not remembered, thus it might
    			actually work differently.  You can use ":&&" to keep
    			the flags.

    						*g&*
    g&			Synonym for ":%s//~/&" (repeat last substitute on all
    			lines with the same flags).
    			Mnemonic: global substitute. {not in Vi}

    						*:snomagic* *:sno*
    :[range]sno[magic] ...	Same as ":substitute", but always use 'nomagic'.
    			{not in Vi}

    						*:smagic* *:sm*
    :[range]sm[agic] ...	Same as ":substitute", but always use 'magic'.
    			{not in Vi}

    							*:s_flags*
    The flags that you can use for the substitute commands:

    [&]	Must be the first one: Keep the flags from the previous substitute
    	command.  Examples:
    		:&&
    		:s/this/that/&
     	Note that ":s" and ":&" don't keep the flags.
    	{not in Vi}

    [c]	Confirm each substitution.  Vim highlights the matching string (with

    	|hl-IncSearch|).  You can type:				*:s_c*
    	    'y'	    to substitute this match
    	    'l'	    to substitute this match and then quit ("last")
    	    'n'	    to skip this match
    	    <Esc>   to quit substituting
    	    'a'	    to substitute this and all remaining matches {not in Vi}
    	    'q'	    to quit substituting {not in Vi}
    	    CTRL-E  to scroll the screen up {not in Vi, not available when
    			compiled without the +insert_expand feature}
    	    CTRL-Y  to scroll the screen down {not in Vi, not available when
    			compiled without the +insert_expand feature}
    	If the 'edcompatible' option is on, Vim remembers the [c] flag and
    	toggles it each time you use it, but resets it when you give a new
    	search pattern.
    	{not in Vi: highlighting of the match, other responses than 'y' or 'n'}

    [e]     When the search pattern fails, do not issue an error message and, in
    	particular, continue in maps as if no error occurred.  This is most
    	useful to prevent the "No match" error from breaking a mapping.  Vim
    	does not suppress the following error messages, however:
    		Regular expressions can't be delimited by letters
    		\ should be followed by /, ? or &
    		No previous substitute regular expression
    		Trailing characters
    		Interrupted
    	{not in Vi}

    [g]	Replace all occurrences in the line.  Without this argument,
    	replacement occurs only for the first occurrence in each line.  If
    	the 'edcompatible' option is on, Vim remembers this flag and toggles
    	it each time you use it, but resets it when you give a new search
    	pattern.  If the 'gdefault' option is on, this flag is on by default
    	and the [g] argument switches it off.

    [i]	Ignore case for the pattern.  The 'ignorecase' and 'smartcase' options
    	are not used.
    	{not in Vi}

    [I]	Don't ignore case for the pattern.  The 'ignorecase' and 'smartcase'
    	options are not used.
    	{not in Vi}

    [p]	Print the line containing the last substitute.
    	{not in Vi}

    [r]	Only useful in combination with ":&" or ":s" without arguments.  ":&r"
    	works the same way as ":~":  When the search pattern is empty, use the
    	previously used search pattern instead of the search pattern from the
    	last substitute or ":global".  If the last command that did a search
    	was a substitute or ":global", there is no effect.  If the last
    	command was a search command such as "/", use the pattern from that
    	command.
    	For ":s" with an argument this already happens:
    		:s/blue/red/
    		/green
    		:s//red/   or  :~   or  :&r
     	The last commands will replace "green" with "red".
    		:s/blue/red/
    		/green
    		:&
     	The last command will replace "blue" with "red".
    	{not in Vi}

    Note that there is no flag to change the "magicness" of the pattern.  A
    different command is used instead.  The reason is that the flags can only be
    found by skipping the pattern, and in order to skip the pattern the
    "magicness" must be known.  Catch 22!

    If the {pattern} for the substitute command is empty, the command uses the
    pattern from the last substitute or ":global" command.  With the [r] flag, the
    command uses the pattern from the last substitute, ":global", or search
    command.

    For compatibility with Vi these two exceptions are allowed:
    "\/{string}/" and "\?{string}?" do the same as "//{string}/r".
    "\&{string}&" does the same as "//{string}/".

    							*E146*
    Instead of the '/' which surrounds the pattern and replacement string, you
    can use any other character, but not an alphanumeric character, '\', '"'' or
    '|'.  This is useful if you want to include a '/' in the search pattern or
    replacement string.  Example:
    	:s+/+//+

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

    					*sub-replace-special* *:s\=*
    When the {string} starts with "\=" it is evaluated as an expression, see
    |sub-replace-expression|.  Otherwise these characters in {string} have a
    special meaning:

    magic	nomagic	  action

      &	  \&	  replaced with the whole matched pattern	     *s/\&*
     \&	   &	  replaced with &

          \0	  replaced with the whole matched pattern	   *\0* *s/\0*
          \1	  replaced with the matched pattern in the first

    		  pair of ()					     *s/\1*
          \2	  replaced with the matched pattern in the first

    		  pair of ()					     *s/\2*

          ..	  ..						     *s/\3*
          \9	  replaced with the matched pattern in the ninth

    		  pair of ()					     *s/\9*
      ~	  \~	  replaced with the {string} of the previous

    		  substitute					     *s~*

     \~	   ~	  replaced with ~				     *s/\~*

          \u	  next character made uppercase			     *s/\u*

          \U	  following characters made uppercase, until \E      *s/\U*

          \l	  next character made lowercase			     *s/\l*

          \L	  following characters made lowercase, until \E      *s/\L*

          \e	  end of \u, \U, \l and \L (NOTE: not <Esc>!)	     *s/\e*

          \E	  end of \u, \U, \l and \L			     *s/\E*
          <CR>	  split line in two at this point

    		  (Type the <CR> as CTRL-V <Enter>)		     *s<CR>*

          \r	  idem						     *s/\r*
          \<CR>	  insert a carriage-return (CTRL-M)

    		  (Type the <CR> as CTRL-V <Enter>)		     *s/\<CR>*
          \n	  insert a <NL> (<NUL> in the file)

    		  (does NOT break the line)			     *s/\n*

          \b	  insert a <BS>					     *s/\b*

          \t	  insert a <Tab>				     *s/\t*

          \\	  insert a single backslash			     *s/\\*
          \x	  where x is any character not mentioned above:
    		  Reserved for future expansion

    Examples:
      :s/a\|b/xxx\0xxx/g		 modifies "a b"	     to "xxxaxxx xxxbxxx"
      :s/\([abc]\)\([efg]\)/\2\1/g	 modifies "af fa bg" to "fa fa gb"
      :s/abcde/abc^Mde/		 modifies "abcde"    to "abc", "de" (two lines)
      :s/$/\^M/			 modifies "abcde"    to "abcde^M"

    Note: In previous versions CTRL-V was handled in a special way.  Since this is
    not Vi compatible, this was removed.  Use a backslash instead.

    command		text	result
    :s/aa/a^Ma/	aa	a<line-break>a
    :s/aa/a\^Ma/	aa	a^Ma
    :s/aa/a\\^Ma/	aa	a\<line-break>a

    (you need to type CTRL-V <CR> to get a ^M here)

    The numbering of "\1", "\2" etc. is done based on which "\(" comes first in
    the pattern (going left to right).  When a parentheses group matches several
    times, the last one will be used for "\1", "\2", etc.  Example:
      :s/\(\(a[a-d] \)*\)/\2/      modifies "aa ab x" to "ab x"

    When using parentheses in combination with '|', like in \([ab]\)\|\([cd]\),
    either the first or second pattern in parentheses did not match, so either
    \1 or \2 is empty.  Example:
      :s/\([ab]\)\|\([cd]\)/\1x/g   modifies "a b c d"  to "ax bx x x"

    Substitute with an expression			*sub-replace-expression*

    When the substitute string starts with "\=" the remainer is interpreted as an
    expression.  This does not work recursively: a substitute() function inside
    the expression cannot use "\=" for the substitute string.

    The special meaning for characters as mentioned at |sub-replace-special| does
    not apply except "<CR>", "\<CR>" and "\\".  Thus in the result of the
    expression you need to use two backslashes get one, put a backslash before a
    <CR> you want to insert and use a <CR> without a backslash where you want to
    break the line.

    For convenience a <NL> character is also used as a line break.  Prepend a
    backslash to get a real <NL> character (which will be a NUL in the file).

    The whole matched text can be accessed with "submatch(0)".  The text matched
    with the first pair of () with "submatch(1)".  Likewise for further
    sub-matches in ().

    Be careful: The separation character must not appear in the expression!
    Consider using a character like "@" or ":".  There is no problem if the result
    of the expression contains the separation character.

    Example:
    	:s@\n@\="\r" . expand("$HOME") . "\r"@
    This replaces an end-of-line with a new line containing the value of $HOME.

    						*:pro* *:promptfind*
    :promptf[ind] [string]
    			Put up a Search dialog.  When [string] is given, it is
    			used as the initial search string.
    			{only for Win32, Motif and GTK GUI}

    						*:promptr* *:promptrepl*
    :promptr[epl] [string]
    			Put up a Search/Replace dialog.  When [string] is
    			given, it is used as the initial search string.
    			{only for Win32, Motif and GTK GUI}

    							*:ret* *:retab*
    :[range]ret[ab][!] [new_tabstop]
    			Replace all sequences of white-space containing a
    			<Tab> with new strings of white-space using the new
    			tabstop value given.  If you do not specify a new
    			tabstop size or it is zero, Vim uses the current value
    			of 'tabstop'.
    			The current value of 'tabstop' is always used to
    			compute the width of existing tabs.
    			With !, Vim also replaces strings of only normal
    			spaces with tabs where appropriate.
    			With 'expandtab' on, Vim replaces all tabs with the
    			appropriate number of spaces.
    			This command sets 'tabstop' to the new value given,
    			and if performed on the whole file, which is default,
    			should not make any visible change.
    			Careful: This command modifies any <Tab> characters
    			inside of strings in a C program.  Use "\t" to avoid
    			this (that's a good habit anyway).
    			":retab!" may also change a sequence of spaces by
    			<Tab> characters, which can mess up a printf().
    			{not in Vi}
    			Not available when |+ex_extra| feature was disabled at
    			compile time.

    							*retab-example*
    Example for using autocommands and ":retab" to edit a file which is stored
    with tabstops at 8 but edited with tabstops set at 4.  Warning: white space
    inside of strings can change!  Also see 'softtabstop' option.

      :auto BufReadPost	*.xx	retab! 4
      :auto BufWritePre	*.xx	retab! 8
      :auto BufWritePost	*.xx	retab! 4
      :auto BufNewFile	*.xx	set ts=4

    ==============================================================================

    5. Copying and moving text				*copy-move*

    							*quote*
    "{a-zA-Z0-9.%#:-"}	Use register {a-zA-Z0-9.%#:-"} for next delete, yank
    			or put (use uppercase character to append with
    			delete and yank) ({.%#:} only work with put).

    							*:reg* *:registers*
    :reg[isters]		Display the contents of all numbered and named
    			registers.  {not in Vi}

    :reg[isters] {arg}	Display the contents of the numbered and named
    			registers that are mentioned in {arg}.  For example:
    				:dis 1a
     			to display registers '1' and 'a'.  Spaces are allowed
    			in {arg}.  {not in Vi}

    							*:di* *:display*
    :di[splay] [arg]	Same as :registers.  {not in Vi}

    							*y* *yank*
    ["x]y{motion}		Yank {motion} text [into register x].  When no
    			characters are to be yanked (e.g., "y0" in column 1),
    			this is an error when 'cpoptions' includes the 'E'
    			flag.

    							*yy*
    ["x]yy			Yank [count] lines [into register x] |linewise|.

    							*Y*
    ["x]Y			yank [count] lines [into register x] (synonym for
    			yy, |linewise|).  If you like "Y" to work from the
    			cursor to the end of line (which is more logical,
    			but not Vi-compatible) use ":map Y y$".

    							*v_y*
    {Visual}["x]y		Yank the highlighted text [into register x] (for
    			{Visual} see |Visual-mode|).  {not in Vi}

    							*v_Y*
    {Visual}["x]Y		Yank the highlighted lines [into register x] (for
    			{Visual} see |Visual-mode|).  {not in Vi}

    							*:y* *:yank*
    :[range]y[ank] [x]	Yank [range] lines [into register x].

    :[range]y[ank] [x] {count}
    			Yank {count} lines, starting with last line number
    			in [range] (default: current line |cmdline-ranges|),
    			[into register x].

    							*p* *put* *E353*
    ["x]p			Put the text [from register x] after the cursor
    			[count] times.  {Vi: no count}

    							*P*
    ["x]P			Put the text [from register x] before the cursor
    			[count] times.  {Vi: no count}

    							*<MiddleMouse>*
    ["x]<MiddleMouse>	Put the text from a register before the cursor [count]
    			times.  Uses the "* register, unless another is
    			specified.  Using the mouse only works when 'mouse'
    			contains 'n' or 'a'.
    			{not in Vi}
    			If you have a scrollwheel and often accidentally paste
    			text, you can use these mappings to disable the
    			pasting with the middle mouse button:
    				:map <MiddleMouse> <Nop>
    				:imap <MiddleMouse> <Nop>
     			You might want to disable the multi-click versions
    			too, see |double-click|.

    							*gp*
    ["x]gp			Just like "p", but leave the cursor just after the new
    			text.  {not in Vi}

    							*gP*
    ["x]gP			Just like "P", but leave the cursor just after the new
    			text.  {not in Vi}

    							*:pu* *:put*
    :[line]pu[t] [x]	Put the text [from register x] after [line] (default
    			current line).  This always works |linewise|, thus
    			this command can be used to put a yanked block as new
    			lines.
    			The register can also be '=' followed by an optional
    			expression.  The expression continues until the end of
    			the command.  You need to escape the '|' and '"''
    			characters to prevent them from terminating the
    			command.  Example:
    				:put ='path' . \",/test\"
     			If there is no expression after '=', Vim uses the
    			previous expression.  You can see it with ":dis =".

    :[line]pu[t]! [x]	Put the text [from register x] before [line] (default
    			current line).

    ["x]]p		    or					*]p* *]<MiddleMouse>*
    ["x]]<MiddleMouse>	Like "p", but adjust the indent to the current line.
    			Using the mouse only works when 'mouse' contains 'n'
    			or 'a'.  {not in Vi}

    ["x][P		    or					*[P*

    ["x]]P		    or					*]P*

    ["x][p		    or					*[p* *[<MiddleMouse>*
    ["x][<MiddleMouse>	Like "P", but adjust the indent to the current line.
    			Using the mouse only works when 'mouse' contains 'n'
    			or 'a'.  {not in Vi}

    You can use these commands to copy text from one place to another.  Do this
    by first getting the text into a register with a yank, delete or change
    command, then inserting the register contents with a put command.  You can
    also use these commands to move text from one file to another, because Vim
    preserves all registers when changing buffers (the CTRL-^ command is a quick
    way to toggle between two files).

    				*linewise-register* *characterwise-register*
    You can repeat the put commands with "." (except for :put) and undo them.  If
    the command that was used to get the text into the register was |linewise|,
    Vim inserts the text below ("p") or above ("P") the line where the cursor is.
    Otherwise Vim inserts the text after ("p") or before ("P") the cursor.  With
    the ":put" command, Vim always inserts the text in the next line.  You can
    exchange two characters with the command sequence "xp".  You can exchange two
    lines with the command sequence "ddp".  You can exchange two words with the
    command sequence "deep" (start with the cursor in the blank space before the
    first word).  You can use the "']" or "`]" command after the put command to
    move the cursor to the end of the inserted text, or use "'[" or "`[" to move
    the cursor to the start.

    						*put-Visual-mode* *v_p* *v_P*
    When using a put command like |p| or |P| in Visual mode, Vim will try to
    replace the selected text with the contents of the register.  Whether this
    works well depends on the type of selection and the type of the text in the
    register.  With blockwise selection it also depends on the size of the block
    and whether the corners are on an existing character. (implementation detail:
    it actually works by first putting the register after the selection and then
    deleting the selection).

    							*blockwise-register*
    If you use a blockwise Visual mode command to get the text into the register,
    the block of text will be inserted before ("P") or after ("p") the cursor
    column in the current and next lines.  Vim makes the whole block of text start
    in the same column.  Thus the inserted text looks the same as when it was
    yanked or deleted.  Vim may replace some <Tab> characters with spaces to make
    this happen.  However, if the width of the block is not a multiple of a <Tab>
    width and the text after the inserted block contains <Tab>s, that text may be
    misaligned.

    Note that after a characterwise yank command, Vim leaves the cursor on the
    first yanked character that is closest to the start of the buffer.  This means
    that "yl" doesn't move the cursor, but "yh" moves the cursor one character
    left.
    Rationale:	In Vi the "y" command followed by a backwards motion would
    		sometimes not move the cursor to the first yanked character,
    		because redisplaying was skipped.  In Vim it always moves to
    		the first character, as specified by Posix.
    With a linewise yank command the cursor is put in the first line, but the
    column is unmodified, thus it may not be on the first yanked character.

    There are nine types of registers:			*registers* *E354*
    1. The unnamed register ""
    2. 10 numbered registers "0 to "9
    3. The small delete register "-
    4. 26 named registers "a to "z or "A to "Z
    5. four read-only registers ":, "., "% and "#
    6. the expression register "=
    7. The selection and drop registers "*, "+ and "~
    8. The black hole register "_
    9. Last search pattern register "/

    1. Unnamed register ""				*quote_quote* *quotequote*
    Vim fills this register with text deleted with the "d", "c", "s", "x" commands
    or copied with the yank "y" command, regardless of whether or not a specific
    register was used (e.g.  "xdd).  An exception is the '_' register: "_dd does
    not store the deleted text in any register.  Vim uses the contents of this
    register for any put command (p or P) which does not specify a register.
    Additionally you can access it with the name '"''.  This means you have to type
    two double quotes.  Writing to the "" register writes to register "0.
    {Vi: register contents are lost when changing files, no '"''}

    2. Numbered registers "0 to "9		*quote_number* *quote0*	*quote1*

    					*quote2* *quote3* *quote4* *quote9*
    Vim fills these registers with text from yank and delete commands.
       Numbered register 0 contains the text from the most recent yank command,
    unless the command specified another register with ["x].
       Numbered register 1 contains the text deleted by the most recent delete or
    change command, unless the command specified another register or the text is
    less than one line (the small delete register is used then).  An exception is
    made for these commands: |%|, |(|, |)|, |`|, |/|, |?|, |n|, |N|, |{| and |}|.
    Register "1 is always used then (this is Vi compatible).  The "- register is
    used as well if the delete is within a line.
       With each successive deletion or change, Vim shifts the previous contents
    of register 1 into register 2, 2 into 3, and so forth, losing the previous
    contents of register 9.
    {Vi: numbered register contents are lost when changing files; register 0 does
    not exist}

    3. Small delete register "-				*quote_-* *quote-*
    This register contains text from commands that delete less than one line,
    except when the command specifies a register with ["x].
    {not in Vi}

    4. Named registers "a to "z or "A to "Z			*quote_alpha* *quotea*
    Vim fills these registers only when you say so.  Specify them as lowercase
    letters to replace their previous contents or as uppercase letters to append
    to their previous contents.

    5. Read-only registers ":, "., "% and "#
    These are '%', '#', ':' and '.'.  You can use them only with the "p", "P",
    and ":put" commands and with CTRL-R.  {not in Vi}

    						*quote_.* *quote.* *E29*
    	".	Contains the last inserted text (the same as what is inserted
    		with the insert mode commands CTRL-A and CTRL-@).  Note: this
    		doesn't work with CTRL-R on the command-line.  It works a bit
    		differently, like inserting the text instead of putting it
    		('textwidth' and other options affect what is inserted).

    							*quote_%* *quote%*
    	"%	Contains the name of the current file.

    							*quote_#* *quote#*
    	"#	Contains the name of the alternate file.

    						*quote_:* *quote:* *E30*
    	":	Contains the most recent executed command-line.  Example: Use
    		"@:" to repeat the previous command-line command.
    		The command-line is only stored in this register when at least
    		one character of it was typed.  Thus it remains unchanged if
    		the command was completely from a mapping.
    		{not available when compiled without the |+cmdline_hist|
    		feature}

    6. Expression register "=				*quote_=* *quote=*
    This is not really a register that stores text, but is a way to use an
    expression in commands which use a register.  The expression register is
    read-only; you cannot put text into it.  After the '=', the cursor moves to
    the command-line, where you can enter any expression (see |expression|).  All
    normal command-line editing commands are available, including a special
    history for expressions.  When you end the command-line by typing <CR>, Vim
    computes the result of the expression.  If you end it with <Esc>, Vim abandons
    the expression.  If you do not enter an expression, Vim uses the previous
    expression (like with the "/" command).  If the "= register is used for the
    "p" command, the string is split up at <NL> characters.  If the string ends in
    a <NL>, it is regarded as a linewise register.  {not in Vi}

    7. Selection and drop registers "*, "+ and "~
    Use these register for storing and retrieving the selected text for the GUI.
    See |quotestar| and |quoteplus|.  When the clipboard is not available or not
    working, the unnamed register is used instead.  {not in Vi}

    Note that there is only a distinction between "* and "+ for X11 systems.  For
    an explanation of the difference, see |x11-selection|.  Under MS-Windows, use
    of "* and "+ is actually synonymous and refers to the |gui-clipboard|.

    						*quote_~* *quote~* *<Drop>*
    The read-only "~ register stores the dropped text from the last drag'n'drop
    operation.  When something has been dropped onto Vim, the "~ register is
    filled in and the <Drop> pseudo key is sent for notification.  You can remap
    this key if you want; the default action (for all modes) is to insert the
    contents of the "~ register at the cursor position.  {not in Vi}
    {only available when compiled with the |+dnd| feature, curently only with the
    GTK GUI}

    Note: The "~ register is only used when dropping plain text onto Vim.
    Drag'n'drop of URI lists is handled internally.

    8. Black hole register "_				*quote_*
    When writing to this register, nothing happens.  This can be used to delete
    text without affecting the normal registers.  When reading from this register,
    nothing is returned.  {not in Vi}

    9. Last search pattern register	"/			*quote_/* *quote/*
    Contains the most recent search-pattern.  This is used for "n" and 'hlsearch'.
    It is writable with ":let", you can change it to have 'hlsearch' highlight
    other matches without actually searching.  You can't yank or delete into this
    register.  {not in Vi}

    							*@/*
    You can write to a register with a ":let" command |:let-@|.  Example:
    	:let @/ = "the"

    If you use a put command without specifying a register, Vim uses the register
    that was last filled (this is also the contents of the unnamed register).  If
    you are confused, use the ":dis" command to find out what Vim will put (this
    command displays all named and numbered registers; the unnamed register is
    labelled '"'').

    The next three commands always work on whole lines.

    :[range]co[py] {address}				*:co* *:copy*
    			Copy the lines given by [range] to below the line
    			given by {address}.

    							*:t*
    :t			Synonym for copy.

    :[range]m[ove] {address}			*:m* *:mo* *:move* *E134*
    			Move the lines given by [range] to below the line
    			given by {address}.

    ==============================================================================

    6. Formatting text					*formatting*

    :[range]ce[nter] [width]				*:ce* *:center*
    			Center lines in [range] between [width] columns
    			(default 'textwidth' or 80 when 'textwidth' is 0).
    			{not in Vi}
    			Not available when |+ex_extra| feature was disabled at
    			compile time.

    :[range]ri[ght] [width]					*:ri* *:right*
    			Right-align lines in [range] at [width] columns
    			(default 'textwidth' or 80 when 'textwidth' is 0).
    			{not in Vi}
    			Not available when |+ex_extra| feature was disabled at
    			compile time.

    							*:le* *:left*
    :[range]le[ft] [indent]
    			Left-align lines in [range].  Sets the indent in the
    			lines to [indent] (default 0).  {not in Vi}
    			Not available when |+ex_extra| feature was disabled at
    			compile time.

    							*gq*
    gq{motion}		Format the lines that {motion} moves over.  The
    			'textwidth' option controls the length of each
    			formatted line (see below).  If the 'textwidth' option
    			is 0, the formatted line length is the screen width
    			(with a maximum width of 79).  {not in Vi}
    			The 'formatoptions' option controls the type of
    			formatting |fo-table|.
    			NOTE: The "Q" command formerly performed this
    			function.  If you still want to use "Q" for
    			formatting, use this mapping:
    				:nnoremap Q gq

    gqgq							*gqgq* *gqq*
    gqq			Format the current line.  {not in Vi}

    							*v_gq*
    {Visual}gq		Format the highlighted text.  (for {Visual} see
    			|Visual-mode|).  {not in Vi}

    							*gw*
    gw{motion}		Format the lines that {motion} moves over.  Similar to
    			|gq| but puts the cursor back at the same position in
    			the text.  However, 'formatprg' is not used.
    			{not in Vi}

    Example: To format the current paragraph use:			*gqap*
    	gqap

    The "gq" command leaves the cursor in the line where the motion command takes
    the cursor.  This allows you to repeat formatting repeated with ".".  This
    works well with "gqj" (format current and next line) and "gq}" (format until
    end of paragraph).  Note: When 'formatprg' is set, "gq" leaves the cursor on
    the first formatted line (as with using a filter command).

    If you want to format the current paragraph and continue where you were, use:
    	gwap
    If you always want to keep paragraphs formatted you may want to add the 'a'
    flag to 'formatoptions'.  See |auto-format|.

    If the 'autoindent' option is on, Vim uses the indent of the first line for
    the following lines.

    Formatting does not change empty lines (but it does change lines with only
    white space!).

    The 'joinspaces' option is used when lines are joined together.

    You can set the 'formatprg' option to the name of an external program for Vim
    to use for text formatting.  The 'textwidth' and other options have no effect
    on formatting by an external program.

    							*right-justify*
    There is no command in Vim to right justify text.  You can do it with
    an external command, like "par" (e.g.: "!}par" to format until the end of the
    paragraph) or set 'formatprg' to "par".

    							*format-comments*
    Vim can format comments in a special way.  Vim recognizes a comment by a
    specific string at the start of the line (ignoring white space).  Three types
    of comments can be used:

    - A comment string that repeats at the start of each line.  An example is the
      type of comment used in shell scripts, starting with "#".
    - A comment string that occurs only in the first line, not in the following
      lines.  An example is this list with dashes.
    - Three-piece comments that have a start string, an end string, and optional
      lines in between.  The strings for the start, middle and end are different.
      An example is the C-style comment:
    	/*
    	 * this is a C comment
    	 */

    The 'comments' option is a comma-separated list of parts.  Each part defines a
    type of comment string.  A part consists of:
    	{flags}:{string}

    {string} is the literal text that must appear.

    {flags}:
      n	Nested comment.  Nesting with mixed parts is allowed.  If 'comments'
    	is "n:),n:>" a line starting with "> ) >" is a comment.

      b	Blank (<Space>, <Tab> or <EOL>) required after {string}.

      f	Only the first line has the comment string.  Do not repeat comment on
    	the next line, but preserve indentation (e.g., a bullet-list).

      s	Start of three-piece comment

      m	Middle of a three-piece comment

      e	End of a three-piece comment

      l	Left adjust middle with start or end (default).  Only recognized when
    	used together with 's' or 'e'.

      r	Right adjust middle with start or end.  Only recognized when used
    	together with 's' or 'e'.

      O	Don't use this one for the "O" command.

      x	Allows three-piece comments to be ended by just typing the last
    	character of the end-comment string as the first character on a new
    	line, when the middle-comment string has already been inserted
    	automatically.  See below for more details.

      {digits}
    	When together with 's' or 'e': add extra indent for the middle part.
    	This can be used to left-align the middle part with the start or end
    	and then add an offset.

      -{digits}
    	Like {digits} but reduce the indent.  This only works when there is
    	some indent for the start or end part that can be removed.

    When a string has none of the 'f', 's', 'm' or 'e' flags, Vim assumes the
    comment string repeats at the start of each line.  The flags field may be
    empty.

    Any blank space in the text before and after the {string} is part of the
    {string}, so do not include leading or trailing blanks unless the blanks are a
    required part of the comment string.

    When one comment leader is part of another, specify the part after the whole.
    For example, to include both "-" and "->", use
    	:set comments=f:->,f:-

    A three-piece comment must always be given as start,middle,end, with no other
    parts in between.  An example of a three-piece comment is
    	sr:/*,mb:*,ex:*/
    for C-comments.  To avoid recognizing "*ptr" as a comment, the middle string
    includes the 'b' flag.  For three-piece comments, Vim checks the text after
    the start and middle strings for the end string.  If Vim finds the end string,
    the comment does not continue on the next line.  Three-piece comments must
    have a middle string because otherwise Vim can't recognize the middle lines.

    Notice the use of the "x" flag in the above three-piece comment definition.
    When you hit Return in a C-comment, Vim will insert the middle comment leader
    for the new line, e.g. " * ".  To close this comment you just have to type "/"
    before typing anything else on the new line.  This will replace the
    middle-comment leader with the end-comment leader, leaving just " */".  There
    is no need to hit BackSpace first.

    Examples:
       "b:*"	Includes lines starting with "*", but not if the "*" is
    		followed by a non-blank.  This avoids a pointer dereference
    		like "*str" to be recognized as a comment.
       "n:>"	Includes a line starting with ">", ">>", ">>>", etc.
       "fb:-"	Format a list that starts with "- ".

    By default, "b:#" is included.  This means that a line that starts with
    "#include" is not recognized as a comment line.  But a line that starts with
    "# define" is recognized.  This is a compromise.

    Often the alignment can be changed from right alignment to a left alignment
    with an additional space.  For example, for Javadoc comments, this can be
    used (insert a backslash before the space when using ":set"):
    	s1:/*,mb:*,ex:*/
    Note that an offset is included with start, so that the middle part is left
    aligned with the start and then an offset of one character added.  This makes
    it possible to left align the start and middle for this construction:
    	/**
    	 * comment
    	 */

    {not available when compiled without the |+comments| feature}

    							*fo-table*
    You can use the 'formatoptions' option  to influence how Vim formats text.
    'formatoptions' is a string that can contain any of the letters below.  The
    default setting is "tcq".  You can separate the option letters with commas for
    readability.

    letter	 meaning when present in 'formatoptions'

    t	Auto-wrap text using textwidth (does not apply to comments)
    c	Auto-wrap comments using textwidth, inserting the current comment
    	leader automatically.
    r	Automatically insert the current comment leader after hitting
    	<Enter> in Insert mode.
    o	Automatically insert the current comment leader after hitting 'o' or
    	'O' in Normal mode.
    q	Allow formatting of comments with "gq".
    	Note that formatting will not change blank lines or lines containing
    	only the comment leader.  A new paragraph starts after such a line,
    	or when the comment leader changes.
    w	Trailing white space indicates a paragraph continues in the next line.
    	A line that ends in a non-white character ends a paragraph.
    a	Automatic formatting of paragraphs.  Every time text is inserted or
    	deleted the paragraph will be reformatted.  See |auto-format|.
    	When the 'c' flag is present this only happens for recognized
    	comments.
    n	When formatting text, recognize numbered lists.  The indent of the
    	text after the number is used for the next line.  The number may
    	optionally be followed by '.', ':', ')', ']' or '}'.  Note that
    	'autoindent' must be set too.  Doesn't work well together with "2".
    	Example:
    		1. the first item
    		   wraps
    		2. the second item
    2	When formatting text, use the indent of the second line of a paragraph
    	for the rest of the paragraph, instead of the indent of the first
    	line.  This supports paragraphs in which the first line has a
    	different indent than the rest.  Note that 'autoindent' must be set
    	too.  Example:
    			first line of a paragraph
    		second line of the same paragraph
    		third line.
    v	Vi-compatible auto-wrapping in insert mode: Only break a line at a
    	blank that you have entered during the current insert command.  (Note:
    	this is not 100% Vi compatible.  Vi has some "unexpected features" or
    	bugs in this area.  It uses the screen column instead of the line
    	column.)
    b	Like 'v', but only auto-wrap if you enter a blank at or before
    	the wrap margin.  If the line was longer than 'textwidth' when you
    	started the insert, or you do not enter a blank in the insert before
    	reaching 'textwidth', Vim does not perform auto-wrapping.
    l	Long lines are not broken in insert mode: When a line was longer than
    	'textwidth' when the insert command started, Vim does not
    	automatically format it.
    m	Also break at a multi-byte character above 255.  This is useful for
    	Asian text where every character is a word on its own.
    M	When joining lines, don't insert a space before or after a multi-byte
    	character.  Overrules the 'B' flag.
    B	When joining lines, don't insert a space between two multi-byte
    	characters.  Overruled by the 'M' flag.
    1	Don't break a line after a one-letter word.  It's broken before it
    	instead (if possible).

    With 't' and 'c' you can specify when Vim performs auto-wrapping:
    value	action
    ""	no automatic formatting (you can use "gq" for manual formatting)
    "t"	automatic formatting of text, but not comments
    "c"	automatic formatting for comments, but not text (good for C code)
    "tc"	automatic formatting for text and comments

    Note that when 'textwidth' is 0, Vim does no formatting anyway (but does
    insert comment leaders according to the 'comments' option).

    Note that when 'paste' is on, Vim does no formatting at all.

    Note that 'textwidth' can be non-zero even if Vim never performs auto-wrapping;
    'textwidth' is still useful for formatting with "gq".

    If the 'comments' option includes "/*", "*" and/or "*/", then Vim has some
    built in stuff to treat these types of comments a bit more cleverly.
    Opening a new line before or after "/*" or "*/" (with 'r' or 'o' present in
    'formatoptions') gives the correct start of the line automatically.  The same
    happens with formatting and auto-wrapping. Opening a line after a line
    starting with "/*" or "*" and containing "*/", will cause no comment leader to
    be inserted, and the indent of the new line is taken from the line containing
    the start of the comment.
    E.g.:
        /*
         * Your typical comment.
         */
        The indent on this line is the same as the start of the above
        comment.

    All of this should be really cool, especially in conjunction with the new
    :autocmd command to prepare different settings for different types of file.

    Some examples:
      for C code (only format comments):
    	:set fo=croq
      for Mail/news	(format all, don't start comment with "o" command):
    	:set fo=tcrq

    Automatic formatting					*auto-format*

    When the 'a' flag is present in 'formatoptions' text is formatted
    automatically when inserting text or deleting text.  This works nice for
    editing text paragraphs.  A few hints on how to use this:

    - You need to properly define paragraphs.  The simplest is paragraphs that are
      separated by a blank line.  When there is no separating blank line, consider
      using the 'w' flag and adding a space at the end of each line in the
      paragraphs except the last one.

    - You can set the 'formatoptions' based on the type of file |filetype| or
      specifically for one file with a |modeline|.

    - Set 'formatoptions' to "aw2tq" to make text with indents like this:

    	    bla bla foobar bla
    	bla foobar bla foobar bla
    	    bla bla foobar bla
    	bla foobar bla bla foobar

    - Add the 'c' flag to only auto-format comments.  Useful in source code.

    And a few warnings:

    - When part of the text is not properly separated in paragraphs, making
      changes in this text will cause it to be formatted anyway.  Consider doing

    	:set fo-=a

    - When using the 'w' flag (trailing space means paragraph continues) and
      deleting the last line of a paragraph with |dd|, the paragraph will be
      joined with the next one.

    - Changed text is saved for undo.  Formatting is also a change.  Thus each
      format action saves text for undo.  This may consume quite a lot of memory.

    - Formatting a long paragraph and/or with complicated indenting may be slow.

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