Here's one that works in theory, but, in practice, doesn't. (I wonder if the Test::Builder owner would want to fix this ... probably not.)

 use Quantum::Superpositions;
 is($var, any('a', 'b'), "it's a or b");
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The idea is that you should be able to do this comparison ... but Test::Builder::_unoverload_str is used to convert the object that any returns into a string ... and that kills all the magic.