This code; 
sub common_path {
    my ($p, $q) = ("$_[0]/", "$_[1]/");
    (my $pos = ($p ^ $q)) =~ /[^\0]/g;
    my $i = 1 + rindex($p, "/", pos($pos) - 2);

    return (
        substr($p, 0, $i),
        substr($p, $i, -1),
        substr($q, $i, -1)
    );
}

[download]
behaves the same as the last one you posted. It's more efficient as well as simpler (according to my benchmarks).

I don't think there's any good reason to use bytes for this. Were you doing it for efficiency reasons?

In reply to Re: Common Substrings by robin
in thread Common Substrings by Anonymous Monk

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