undef and "" are indeed different in Perl, but both are boolean false, so the test can be simplified to:

if (!$string) {
}

[download]

See perlsyn#Truth-and-Falsehood.

Update: Except that "0" is also false, so if that’s a possibility, prefer BrowserUk’s solution, below.

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: Undefined vs empty string by Athanasius
in thread Undefined vs empty string by Anonymous Monk

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