C:\>perl
use strict;
use warnings;
my $x = 2;
my $test = 123 if $x;
print $test;
^Z
123
C:\>perl
use strict;
use warnings;
my $x = 0;
my $test = 123 if $x;
print $test;
^Z
Use of uninitialized value in print at - line 5.

C:\>