Hello liorlew, and welcome to the Monastery!

choroba and stevieb have answered your question, but I want to point out that Perl has the useful logical defined-or operator //, which allows you code this more concisely and expressively:

use strict;
use warnings;

my $undefvar;

...

my $newvar = $undefvar // 0;

[download]

See perlop#Logical-Defined-Or.

Hope that helps,

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

In reply to Re: if defined not working by Athanasius
in thread if defined not working by liorlew

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