Then look again.

Are you are your saying your comments are wrong 

/$pat1/ && /$pat2/;          # Sets $1 (twice).
/$pat1/ && /$pat2/;          # Sets $1.

[download]
/^(?=.*?$pat1)(?=.*?$pat2)/; # Sets $1 and $2.
/^(?=.*?$pat1)(?=.*?$pat2)/; # Doesn't set $1 or $2.

[download]

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]

I swear I checked that a million times first. I'm blind! Needless to say, it would have been clearer to change $_ instead.

In reply to Re^9: AND and OR on Regular Expressions by ikegami
in thread AND and OR on Regular Expressions by vitoco

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