A few examples of how to use :g in vim

This vim tip of the day is really good. I use the :g/pattern/d command occasionally, but there is a lot more possible. Here’s the tip:


VimTip 227: Power of :g
http://vim.sourceforge.net/tip_view.php?tip_id=

:g is something very old and which is very powerful. I just wanted to illustrate the use of it
with some examples. Hope, it will be useful for someone.

Brief explanation for ":g"
-------------------------
Syntax is:
:[range]:g//[cmd]
You can think the working as, for the range (default whole file), execute
the colon command(ex) "cmd" for the lines matching . Also, for all
lines that matched the pattern, "." is set to that particular line (for
certain commands if line is not specified "." (current line) is assumed).

Some examples
-------------
Display context (5 lines) for all occurences of a pattern
:g//z#.5
:g//z#.5|echo "=========="
<< same as first, but with some beautification >>
Delete all lines matching a pattern
:g//d
Delete all blank lines (just an example for above)
:g/^\s*$/d
Double space the file
:g/^/pu =\"\n\"
:g/^/pu _
<< the above one also works >>
Copy all lines matching a pattern to end of file
:g//t$
Yank all lines matching a pattern to register 'a'
0"ay0:g//y A
Increment the number items from current line to end-of-document by one
:.,$g/^\d/exe "normal! \"
Comment (C) lines containing "DEBUG" statements
g/^\s*DEBUG/exe "norm! I/* \A */\"
A Reverse lookup for records
(eg: An address book, with Name on start-of-line and fields after a space)
:g/?^\w?p "if only name is interested
:g//ka|?^\w?p|'ap "if name and the lookup-line is interested
:g//?^\w?|+,/^[^ ]/-1p "if entire record is interested
Reverse a file (just to show the power of 'g')
:g/^/m0

Foot note 1: use :v to negate the search pattern
Foot note 2: Some explanation of commonly used commands with :g
:2,8co15 => Copy lines 2 through 8 after line 15
:4,15t$ => Copy linesa 4 through 15 towards end of document (t == co)
:-t$ => Copy previous line to end of document
:m0 => Move current line to the top of the document
:.,+3m$-1 => Move current line through cur-line+3 to the last but one line
of the document
Foot note 3: Commands used with :g are ex commands, so a help search should
be,
:help :
eg. :help :k

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matt

My name is Matt Wilson and I live in Cleveland Heights, Ohio. I love random emails from strangers, so get in touch! matt@tplus1.com.