It's a hash slice.

It fills the hash %exts with the contents of your @exts array. The keys are set to the values in @exts, and the values in the hash are set to undef. That's why you need to test for exists rather than "truth"; because the values aren't "true", but the keys do exist.

In reply to Re: Re: Re: Better way to search? by btrott
in thread Better way to search? by r.joseph

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