#define_method vs ActiveSupport::StringInquirer

a.rb

class A
  attr_accessor :kind

  def initialize(kind)
    self.kind = kind
  end

  def one?   ; self.kind == 'one'   ; end
  def two?   ; self.kind == 'two'   ; end
  def three? ; self.kind == 'three' ; end
  def three? ; self.kind == 'four'  ; end
  def five?  ; self.kind == 'five'  ; end
end

b.rb

class B
  attr_accessor :kind

  def initialize(kind)
    self.kind = kind
  end

  %w[one two three four five].each do |kind|
    define_method("#{kind}?") do
      self.kind == kind.to_s
    end
  end
end

c.rb

class C
  attr_accessor :kind

  def initialize(kind)
    self.kind = ActiveSupport::StringInquirer.new(kind)
  end
end

results.txt

# ruby -rubygems -I. setup.rb

##################################################################
# ruby 1.8.7 (2010-12-23 patchlevel 330) [x86_64-darwin10.5.0]
##################################################################
Rehearsal --------------------------------------------------------
A (explicit methods)   0.150000   0.030000   0.180000 (  0.176056)
B (define_method)      0.180000   0.040000   0.220000 (  0.213807)
C (string inquirer)    0.070000   0.030000   0.100000 (  0.098579)
----------------------------------------------- total: 0.500000sec

                           user     system      total        real
A (explicit methods)   0.150000   0.020000   0.170000 (  0.176828)
B (define_method)      0.180000   0.040000   0.220000 (  0.217881)
C (string inquirer)    0.060000   0.020000   0.080000 (  0.094166)

##################################################################
# ruby 1.9.2p180 (2011-02-18 revision 30909) [x86_64-darwin10.6.0]
##################################################################
Rehearsal --------------------------------------------------------
A (explicit methods)   0.460000   0.140000   0.600000 (  0.596940)
B (define_method)      0.370000   0.090000   0.460000 (  0.467380)
C (string inquirer)    0.200000   0.070000   0.270000 (  0.269189)
----------------------------------------------- total: 1.330000sec

                           user     system      total        real
A (explicit methods)   0.450000   0.140000   0.590000 (  0.590053)
B (define_method)      0.370000   0.100000   0.470000 (  0.473767)
C (string inquirer)    0.200000   0.060000   0.260000 (  0.264523)


##################################################################
# jruby 1.6.0 (ruby 1.8.7 patchlevel 330) (2011-03-15 f3b6154)
# (Java HotSpot(TM) 64-Bit Server VM 1.6.0_24) [darwin-x86_64-java]
##################################################################
Rehearsal --------------------------------------------------------
A (explicit methods)   0.622000   0.000000   0.622000 (  0.621000)
B (define_method)      0.494000   0.000000   0.494000 (  0.494000)
C (string inquirer)    0.221000   0.000000   0.221000 (  0.221000)
----------------------------------------------- total: 1.337000sec

                           user     system      total        real
A (explicit methods)   0.384000   0.000000   0.384000 (  0.384000)
B (define_method)      0.456000   0.000000   0.456000 (  0.456000)
C (string inquirer)    0.199000   0.000000   0.199000 (  0.199000)


##################################################################
# rubinius 1.2.4dev
# (1.8.7 090c86c6 yyyy-mm-dd) [x86_64-apple-darwin10.7.0]
##################################################################
Rehearsal --------------------------------------------------------
A (explicit methods)   0.461322   0.051510   0.512832 (  0.514030)
B (define_method)      0.387867   0.050668   0.438535 (  0.441115)
C (string inquirer)    0.287570   0.045437   0.333007 (  0.333381)
----------------------------------------------- total: 1.284374sec

                           user     system      total        real
A (explicit methods)   0.417872   0.051728   0.469600 (  0.469912)
B (define_method)      0.435688   0.050810   0.486498 (  0.488859)
C (string inquirer)    0.335798   0.045136   0.380934 (  0.380966)

setup.rb

require 'benchmark'
require 'active_support/string_inquirer'

TIMES = 1_000
Benchmark.bmbm do |x|
  x.report('A (explicit methods)') do
    TIMES.times { load 'a.rb' }
  end

  x.report('B (define_method)') do
    TIMES.times { load 'b.rb' }
  end

  x.report('C (string inquirer)') do
    TIMES.times { load 'c.rb' }
  end
end