use warnings;
can cause that warning message. but not fatal.
usually happens with codes like
use warnings;
my %hash;
if ($hash{'word'} =~ /world/) {
}

[download]
$hash{word} is not defined and will cause that warning.
Make sure $hash{word} holds a valid value before using it or it will give you a warning.

In reply to Re: Perl CGI.PM: Use of uninitialized value $vals by jsteng
in thread Perl CGI.PM: Use of uninitialized value $vals by Anonymous Monk

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