From: Benoit Daloze Date: 2011-06-24T01:00:21+09:00 Subject: [ruby-core:37328] Re: [Ruby 1.9 - Feature #4917][Rejected] NilClass#to_ary On 22 June 2011 19:55, Marc-Andre Lafortune wrote: > The method `to_ary` is for classes that can be implicitly converted to an Array. This doesn't apply to NilClass. > > I'm also highly sceptical as to the actual real life impact of such an optimization. I agree with you, such optimization is not worth it. But, for the sake of curiosity, I did my own benchmark. The numbers are (optArray doing the nil check, for 1 000 000 calls): Array(nil) 0.487444 optArray(nil) 0.234128 Array(Object.new) 0.462688 optArray(Object.new) 0.467910 It is 2 times faster for nil, and does not seem to impact the performance for other objects. But the real gain is 0.2s on 1 million calls, which should never happen in real life (or then it would be insignificant compared to the total time to run).