hash_default.rb

require 'bench_press'
extend BenchPress

author 'Ken Collins'
summary "Check and populate a options hash"

reps 100_000

measure "Hash#key?" do
  o = {}
  o[:d] = true unless o.key?(:d)
end

measure "Hash#merge!" do
  {}.merge!(:key => :value)
end

measure "Hash#[]= Standard" do
  {}[:key] = :value
end

measure "Hash#[]= Tricky" do
  {}.[]=(:key, :value)
end



=begin

ruby 1.8.7 (2010-04-19 patchlevel 253) [i686-darwin10.4.0], MBARI 0x6770, Ruby Enterprise Edition 2010.02
----------------------------------------------------------------

    Hash#[]= Standard    0.215189933776855 secs    Fastest
    Hash#[]= Tricky      0.21603798866272  secs    0% Slower
    Hash#merge!          0.309281826019287 secs    30% Slower
    Hash#merge           0.384943962097168 secs    44% Slower

ruby 1.8.7 (2010-08-16 patchlevel 302) [i686-darwin10.4.0]
----------------------------------------------------------------

    Hash#[]= Standard    0.150069952011108 secs    Fastest
    Hash#[]= Tricky      0.152034044265747 secs    1% Slower
    Hash#merge!          0.227920055389404 secs    34% Slower
    Hash#merge           0.303483963012695 secs    50% Slower

ruby 1.9.1p378 (2010-01-10 revision 26273) [i386-darwin10.4.0]
--------------------------------------------------------------

    Hash#[]= Tricky      0.103008031845093 secs    Fastest
    Hash#[]= Standard    0.103388071060181 secs    0% Slower
    Hash#merge!          0.201750993728638 secs    48% Slower
    Hash#merge           0.23440408706665  secs    56% Slower

ruby 1.9.2p0 (2010-08-18 revision 29036) [x86_64-darwin10.4.0]
--------------------------------------------------------------

    Hash#[]= Tricky      0.10367894172668457 secs    Fastest
    Hash#[]= Standard    0.10428905487060547 secs    0% Slower
    Hash#merge!          0.18069767951965332 secs    42% Slower
    Hash#merge           0.20720911026000977 secs    49% Slower


=end