Hi!

I've been trying to write a script to generate some useful output based on a log file, and I ran into the issue mentioned in this thread.

http://www.nntp.perl.org/group/perl.perl6.language.regex/2000/12/msg507.html

Specifically, the problem I'm trying to solve involves matching a group of log lines.

For example:

KEY
blah
blahblah
KEY
blah ah
other random stuff
KEY
blah ha
other random stuff
PATTERN
asdf
KEY
fdas
PATTERN

[download]

I want to match each PATTERN, but have the match also include the most recent preceeding KEY (and everything in between). So these are the two matches I'm interested in:

KEY
blah ha
other random stuff
PATTERN

[download]

KEY
fdas
PATTERN

[download]

If I do something like KEY.*PATTERN the entire contents get the match, and if I do KEY.*?PATTERN it matches everything from the first KEY to the first PATTERN. I've also tried .*KEY.+?PATTERN which just matches the very last group.

If you've got any insight it would be greatly appreciated.

Thanks.

In reply to pattern matching (greedy, non-greedy,...) by cacophony777

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