Re: Feature Request: DeleteLinesNotMatching

[Chip Seraphine]

Daniel Pittman wrote:
> 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

Almost all (or maybe just 'all') of the 'one-sided' logical editfiles 
actions could use a mirror action, IMHO.  BeginGroupIfLineMatching would 
be huge, too....

I've generally gotten by such things by either writing a module to do it 
in perl/awk/shell/whatever or using a kludgey (but faster) trick such as 
  "ReplaceAll x With y" to get the file in a state that can be managed 
with the available tools.  Be warned, though, cfengine will sometimes 
tell you that such things are not convergent, even when it is apparent 
(to a human) that they are.  This has happened to me when doing things 
like converting tabs to spaces so that I could use SplitOn stuff...