From: Csaba Henk <csaba@..._for_avoiding_spam.org>
Date: 2005-02-28T16:55:00+09:00
Subject: Re: for vs. each

On 2005-02-27, Robert Klemme <bob.news@gmx.net> wrote:
>
> "Fear Dubh" <feardubh@spam.spam> schrieb im Newsbeitrag
> news:cvslbj$9ns$1@reader01.news.esat.net...
>> Does each have a fatter frame then?
>> Is "for ... in ... do ..." more efficient?
>
> I would believe not, but you can test this yourself (hint "ruby -r profile"
> and module Benchmark).

$ ruby -v
ruby 1.8.2 (2004-12-25) [i386-linux]
ruby -rbenchmark -e 'n=10**6; [
  proc{ (0...n).each{|x| x} },
  proc{ for x in 0...n; x ;end },
  proc{ n.times{|x| x} }
].each {|pr| puts Benchmark.measure(&pr) }'
  0.370000   0.000000   0.370000 (  0.376541)
  0.320000   0.000000   0.320000 (  0.339880)
  0.370000   0.000000   0.370000 (  0.391311)

So for is slightly faster. But see, do you wonder what happens if you
execute the above three benchmarks in reverse order? Just replace the
"each" (after the three-element array) with "reverse_each"... ;)

Csaba