When you use "==", both the left and right sides are evaluated in numeric context. Since, in numeric context, " " and 0 are equivalent (and are also numerically equivalent to both undef and "" btw), your 'if' and 'elsif' conditions are effectively identical.

That is, if $val == " " is true, then so is $val == 0, and vice-versa

Cheers,
Rob

In reply to Re: How can I differentiate between 0 and whitespace in Perl? by syphilis
in thread How can I differentiate between 0 and whitespace in Perl? by boom

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