sub match_in_between {
    my ($str, $r1, $r2, $n) = @_;

    return undef unless
      4 == grep { defined() } ($str, $r1, $r2, $n);

    my ($match, $end) = ($str =~ /$r1((?:.*?($r2)){$n})/);
    return "" unless defined($match);
    return substr($match, 0, rindex($match, $end));
}

print match_in_between("abcbcbc", qr/a/, qr/c/, 3);    # bcbcb
print match_in_between("cccabcbcbc", qr/a/, qr/c/, 3); # bcbcb
print match_in_between("abcbxbcff", qr/a/, qr/b./, 3); # bcbx

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In reply to Re: Regex text extraction b/w first intance of pattern X and third instance of pattern Y. by repellent
in thread Regex text extraction b/w first intance of pattern X and third instance of pattern Y. by cdherold

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