Write your own function. (This one is adapated from Test::Builder, the basis for Test::More's is() test.) 
sub is_eq {
    my ($l, $r) = @_;
    if (defined $l && defined $r) {
        return $l eq $r;
    }
    else {
        return !defined $l && !defined $r;
    }
}

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Updated: Fixed typo in transcription from Test::Builder::is_eq()

My wife's blog

In reply to Re: undef-safe equality by dragonchild
in thread undef-safe equality by hubb0r

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