It's what's called the Schwartzian Transform, I believe. You can check it out here: http://www.perlmonks.com/index.pl?node_id=115828 or http://www.perlmonks.com/index.pl?node_id=9108 ...

It's designed to make the sort more efficient, saving on memory and what not ... but don't let me explain it, do a search on the site (there are hundreds of discussions about it)

In reply to Re: Mapping, Sorting, Mapping on hash-keys by dimmesdale
in thread Mapping, Sorting, Mapping on hash-keys by Tomte

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