Answer 10

This is a special case of the Schwartzian Transform known as a "packed-default sort," which eliminates the custom sort subroutine altogether.

Generally, any technique that allows you to use the native comparison of the sort function will be the best performer, especially on large data sets. Remember, any inefficiencies in the pre- and post-processing are O(N), while the sort itself is O(N log N).

See www.effectiveperl.com/recipes/sorting.html and www.sysarch.com/perl/sort_paper.html for some discussion. Search for "packed-default sort" in the latter.

Contributor: Dave Tweed

Published: August-2002