Add a function to search for lines which don't match a regular expression
For instance, using regular expressions, it's possible to check if a line contains a valid e-mail address. But you can't create a regular expression which matches invalid e-mail addresses.
You can find a lines which do not match to specific regexp. Check my post in HippoEDIT forum: http://forum.hippoedit.com/?/topic,94.msg3574.html#msg3574