Hi Monks, looking for Wisdom about nested matches. I have following string:
$fc = '#4 
r0 !
r1 !
r2 !
#5
r3 !
r4 !
r5 !
';

[download]
What I want to obtain is:
#4
r2 !
#5 
r5 !

[download]
.. which means that foreach (#\d+) and ((\S+\s+\S+\s+)*) match, I need to take first item and then last item of the 2nd and nested match. Following code works:
while ($fc =~ /#(\d+)\s+(\S+\s+\S+\s+)*)/g ) {
    $time = $1; $list = $2;
    @rlist = split /\n/, $list;
    $ofc .= "#$time\n$rlist[$#rlist]\n";
}

[download]
.. but what I don't like is that I need to store the new string into a second var like "$ofc". Is there a way to remedy 2nd var and thus to reduce this loop into one single substitution?: $fc =~ s/(#\d+)\s+((\S+\s+\S+\s+)*)/$1$&/g; ... which doesn't do the job I want. Holy monks, do I want too much? Could substitue s///g be faster than global matching for this case?

In reply to substitute instead global matching for nested matches by utku

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