Hi Anonymous Monk,
I am also considering capturing the beginning and ending index of each match (reading left to right)
You can also do like so, using while loop and index function: 

use warnings;
use strict;

my $dna = 'xxxxxxpecbcbccrlxxxxxxpeeeerlxxxxxplxxxxxPeRLxxxx';
my $re  = qr/p.*?l/i;

while ( $dna =~ m[($re)]g ) {
    my $beg = index( $dna, $1 );
    my $len = length($1);
    print join " " => $1, $beg, $beg + ($len -1), $/; # updated
}

[download]
which produces.. 
pecbcbccrl 6 15 
peeeerl 22 28 
pl 34 35 
PeRL 41 44

[download]
#Update: Correction of length of each string longer by one, as rightly pointed out by hdb

If you tell me, I'll forget.
If you show me, I'll remember.
if you involve me, I'll understand.
--- Author unknown to me

In reply to Re: Find and extract substring(s) within larger string. by 2teez
in thread Find and extract substring(s) within larger string. by Anonymous Monk

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