For some weird reason I was expecting reverse_each to be slower than each, so I decided that reversing once and eaching multiple times would be faster than multiple reverse_eaching - Benchmarking killed that myth though. The saving however, is in the order of nanoseconds, as the reverse only happens once. Reversing an array with 10 elements took about a millionth of second on my machine. Considering you're going to be iterating over 3.6 million permutations, which takes somewhere in the order of 3 minutes, I decided that extra optimisation wasn't necessary =) I would have preferred if ((size-1)..0).each actually iterated, but them's the breaks. > -----Original Message----- > From: Sean O'Halpin [mailto:sean.ohalpin / gmail.com] > Sent: Monday, 7 November 2005 11:36 AM > To: ruby-talk ML > Subject: Re: Fun with Permutations (including new change for Facets) > > On 11/7/05, Daniel Sheppard <daniels / pronto.com.au> wrote: > > s = (0...size).to_a.reverse > > ... > > break if s.each { |i| > > Did you know there is a reverse_each? Might shave off a > millisecond or two ;) > > Regards, > > Sean > > > ##################################################################################### This email has been scanned by MailMarshal, an email content filter. #####################################################################################