Then look again.

Are you are your saying your comments are wrong

/$pat1/ && /$pat2/;          # Sets $1 (twice).
/$pat1/ && /$pat2/;          # Sets $1.
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/^(?=.*?$pat1)(?=.*?$pat2)/; # Sets $1 and $2.
/^(?=.*?$pat1)(?=.*?$pat2)/; # Doesn't set $1 or $2.
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And that you repeated 4 lines of code for nothing?

    $pat1 = "(foo)";
    $pat2 = "(bar)";
    /$pat1/ && /$pat2/;
    /^(?=.*?$pat1)(?=.*?$pat2)/;

    $pat1 = "(foo)";
    $pat2 = "(baz)";
    /$pat1/ && /$pat2/;
    /^(?=.*?$pat1)(?=.*?$pat2)/;
[download]