From: Martin DeMello <martindemello@...>
Date: 2003-05-30T16:26:42+09:00
Subject: Re: Iteration - last detection

dblack@superlink.net wrote:
>  module Enumerable
>    def each_with_last
>      n = -1
>      each { n += 1 }
>      each_with_index {|e,i| yield(e, i == n)}
>    end
>  end
> 
> It benchmarks a bit faster than yours, for arrays of size 10 to 10000,
> but not wildly so.

My flag version benchmarks fater still

user     system      total        real
flag:       146.570000   0.270000 146.840000 (167.307243)
index:      190.220000   1.170000 191.390000 (219.334280)

Also, if we're really bumming cycles (and depending on how differently
you want to treat the last element), you could yield 0..n-1 and return
n, saving the two-valued yield and the test in the client method.

martin