Feature Request: DeleteLinesNotMatching

[Daniel Pittman]

One of the common problems that I am having with the cfengine
'editfiles' operation is to make sure that something that isn't
permitted in a file is removed.

This would be made much easier by having a 'DeleteLinesNotMatching
<regexp>' operation available.

Any thoughts on this for a future version?
    Daniel

-- 
We must put aside the weapons of our minds, 
cross the no man's land come with empty hands. 
Overcome the fear to drop the last defense, 
speak forbidden words reach out beyond ourselves.
        -- Covenant, _Wall Of Sound_