OK, "wrong" was probably a too strong word (I'm not a native speaker of English). But compare the following two expressions, both being "right" from the test driven perspective: 
    # 1
    $x = 'a' . $y . $z->[1];

    # 2
    $x = join q(), scalar(chr 97), $y, (@$z)[1], '';

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In reply to Re^3: Question about regex performance by choroba
in thread Question about regex performance by ted.byers

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