if($1, $2, $3, $4) 

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 if ($1 && $2 && $3 && $4)
[download]

Make that change and it'll be fine. You weren't doing what you thought you were doing. :-)

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We are the carpenters and bricklayers of the Information Age.

The idea is a little like C++ templates, except not quite so brain-meltingly complicated. -- TheDamian, Exegesis 6

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.