From: murphy <murphy@...>
Date: 2007-07-06T20:13:00+09:00
Subject: Optimizing Symbol#to_proc

Greetings to the list!

I think Symbol#to_proc will get used a lot in the future, and since it's
ususally applied to Enumerations, the proc gets called a lot.

The implementation is much faster than the old Ruby code versions, but
compared to a hand-written inline block, it's still slow:

  Benchmark.bm(20) do |bm|
    a = Array.new(1000, nil)
    bm.report 'to_proc' do
      1000.times do
        a.each(&:nil?)
      end
    end
    bm.report 'block' do
      1000.times do
        a.each { |x| x.nil? }
      end
    end
  end

  # >>                           user     system      total        real
  # >> to_proc               0.620000   0.000000   0.620000 (  0.624540)
  # >> block                 0.250000   0.010000   0.260000 (  0.253732)

(Ruby 1.9 from today, MacBook, OSX)

Maybe this is a good place for more optimization, or even VM magic?
[murphy]