http://vim.wikia.com/wiki/Delete_all_lines_containing_a_pattern
The ex command g is very useful for acting on lines that match a pattern. You can use it with the d command, to delete all lines that contain a particular pattern, or all lines that do not contain a pattern.
For example, to delete all lines containing "profile" (the first command is optional; it shows the lines that the second command will delete):
:g/profile :g/profile/d
More complex patterns can be used, such as deleting all lines that are empty or that contain only whitespace:
:g/^s*$/d
To delete all lines that do not contain a pattern, use g!, like this command to delete all lines that are not comment lines in a Vim script:
:g!/^s*"/d
Note that g! is equivalent to v, so you could also do the above with:
:v/^s*"/d
The next example shows use of | ("or") to delete all lines except those that contain "error" or "warn" or "fail" (:help pattern):
:v/error|warn|fail/d
See also
Edit
- Remove unwanted empty lines
- Filter buffer on a search result
- Folding with Regular Expression
- Power of g
CommentsEdit
Can we remove all even numbered lines in a file using this feature. can we do some kind of math in the pattern. (ex: =line(".") % 2)
Not really, but you can do that in two steps:
:g/.*/if line('.')%2|call setline(line('.'), '===delete===')|endif
:g/^==delete==$/d
If you simply put delete inside the if statement all the lines will be deleted. Much faster solution is to record a macro "ddj" and play it over the file. You could delete lines from several different ranges:
:let range = range(10,15)+range(20,25)+range(30,35)
:g/.*/if index(range, line('.')) != -1|call setline(line('.'), '===delete===')|endif
:g/^===delete===$/d
But again I think the faster way to do that is to use :[range]d several times.