You forgot undef, which is also false.

To check to see if there are characters in $script::debug that aren't printing you can always check the length of $string::debug.

Update: Just thought of this: are you putting a \n in the variable? Because "0\n" is not "0".

In reply to Re: What are all the false values in Perl ((conditional by swiftone
in thread What are all the false values in Perl ((conditional, boolean, whitespace, unprintable characters) by princepawn

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