Look more carefully. %foo is not empty. It was initialized with curly brackets -- almost ALWAYS a sign that the author made a mistake. Not a very humorous answer, but Wayne Jarvis is not paid to be funny.

:|

Still however -- the code indeed is a no op in terms of "useful" work. One needs to explicitly require %foo as a scalar: 
unlink scalar %foo;

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In reply to Re^2: The strangest use of unlink I know of by Anonymous Monk
in thread The strangest use of unlink I know of by vrk

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