hangon,
Several modules in perl 5 provide this functionality. Currently, Perl 6 will provide set operations and junctions natively. If you do not see how this answers your question I hope you go exploring for more information on your own. You never know what useful information you will find along the way.

Cheers - L~R

In reply to Re: *IN* Operator for the Perl wish list by Limbic~Region
in thread *IN* Operator for the Perl wish list by hangon

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