' ' is true in Perl. Only 0, '0', '', and undef are false (see What is true and false in Perl?). The word "defined" has a different meaning, too (see defined).

If you are only interested in values that contain a digit, you can use a regular expression: /[0-9]/.

لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

In reply to Re: Something is defined when it shouldn't be? by choroba
in thread Something is defined when it shouldn't be? by tnyflmngs

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