You mean something akin to the "identity equality" operators that I think Python, Ruby, and JavaScript have? 
if ($x === $y) { ... }
if ($a !== $b) { ... }

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No, as far as I know, there's nothing for that right now, although Perl 6 probably has it.
Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re: Comparing undefined values by japhy
in thread Comparing undefined values by Ovid

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