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: