Benchmark comparing class_eval to define_method when defining methods

meta_method_definition_benchmark.rb

require "benchmark"
COUNT = 1000
Benchmark.bmbm do |test|
  
  test.report "class eval" do
    
    class ClassEvalClass;end
    
    COUNT.times do |i|
      ClassEvalClass.send :class_eval, "def method_no_#{i}; return #{i} ;end"
      d = ClassEvalClass.new
      d.send("method_no_#{i}")
    end
    
  end
  
  test.report "define_m" do
    
    class DefineMClass;end
    
    COUNT.times do |i|
      DefineMClass.send :define_method, "method_no_#{i}" do
        return i
      end
      d = DefineMClass.new
      d.send("method_no_#{i}")
    end
    
  end
  
end

# Rehearsal ----------------------------------------------
# class eval   0.020000   0.000000   0.020000 (  0.017990)
# define_m     0.000000   0.000000   0.000000 (  0.006061)
# ------------------------------------- total: 0.020000sec

#                 user     system      total        real
# class eval   0.020000   0.000000   0.020000 (  0.018008)
# define_m     0.010000   0.000000   0.010000 (  0.004436)