> am I an idiot or is this a common issue that I should be handling differently?

No you are not an idiot, it's just that different people have different understandings about a true scalar.

This means you need to be explicit what you exactly want to test.

• if (defined($string)) tells me that I didn't get undef
• if(length($string)) is testing against empty strings (NB: not the same like undef !!!)
• if($scalar) is testing against Perl's concept of truthiness.

Background: Perl is designed such that scalars are transparent to their C type, i.e. no matter if the 0 is internally an integer, float or string. °

Hence the inner representation of a scalar can change without effecting the boolean context.

NB: If you really need an explicit string type which is only false when empty, you are free to create your own "string" object and overload it's bool behaviour.

update

°) in other languages with explicit types you are forced to transform a number inside a string into an int or float before using numeric operations.

For instance in Python

• a + b can be a string concat or a numeric addition depending on the type, in Perl it's always only an addition.
• and 3/2 will yield 1 because it's an integer operation.

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