So... I've been working on this for a couple days now and I'm getting nowhere. I'm a bit of a perl novice, but here's the situation. I'm trying to parse a massive scalar that contains a log file. I need to build an expression to extract the last set of data, which will be marked with a header and footer. I've figured out how to get there by converting the scalar to an array, going through it line by line until I find my matches and verify that they are the last ones etc... but it winds up taking a lot of processing time to do it that way. I'm hoping that the proper regular expression will be able to find my result without having to munch through the entire file so many times.

Here's the example code I've been working with to test my regular expression. 

my $string = "
start:
end:

test
code
start: real
1
end: real
with
start: real
repeating newlines
and more than
start: real
one

instance
end: real
of the 
start: real
desired
string


end: real


start:
end:";

if ($string =~/(start: real)((.|\n)*(?!start: )(.|\n)*)*(end: real)/){
    print "$&";
    }

[download]

The goal is it should match 

start: real
desired
string


end: real

[download]

and nothing else, but right now it matches from the first "start: real" to the "last end: real".

I can see how to make the expression non-greedy, which would make it possible to capture only the first set, but I don't know how to capture only the last one.

In reply to Regex to find the last matching set in a long scalar by superwombat

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