If you can give details about exactly what you're trying to accomplish, it would help.
Do you mean you only want "test" to appear and not "test test"? Is that what you mean by once? Or what?
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SladeKraven:
Just a note that was pointed out to me in the past... !$3 would trigger if $3 equals $null, but it would also trigger if $3 equals $false, and one other situation that I can't think of right now. So, depending what's being done, using ($3 == $null) may be the best way even if it's a little longer code.
