I am not sure that you are making this harder than it is. If you always have an end marker following a start marker than it is trivial. If on the other hand, you may see something like:

"start b2 start b2 end start b2 b2 end"

then the only way I see to do it would be to use functions like index and substr to iterate over the string removing pieces of it until it is in the form you want before regex'ing it.

If on the slight chance you will always see a start marker, some text that does NOT include another start marker, and then an end marker, you can simply do this: 

my $str = "start b2 end start b2 b2 end start b2 end";
if ($str =~ /.*start((.*?b2.*?b2).*?)end/) {
 print "$1 is between \"start\" and \"end\"\n";
}

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In reply to Re: Keeping lookahead assertion from looking to the end of the string? by Limbic~Region
in thread Keeping lookahead assertion from looking to the end of the string? by swackerl

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