dm_vs_ce.rb

require "benchmark"

N = 300_000
Benchmark.bmbm do |x|
  x.report("define_method") do
    class Foo
      (1..N).each do |i|
        define_method "method_#{i}".to_sym do
          "bla_#{i}"
        end
      end
    end
  end

  x.report("class_eval   ") do
    class Bar
      (1..N).each do |i|
        class_eval <<-METHOD
          def method_#{i}
            "blah_#{i}"
          end
        METHOD
      end
    end
  end
end

__END__
Rehearsal -------------------------------------------------
define_method   5.830000   0.240000   6.070000 (  6.081396)
class_eval      5.300000   0.100000   5.400000 (  5.396433)
--------------------------------------- total: 11.470000sec

                   user     system      total        real
define_method  15.240000   0.020000  15.260000 ( 15.253883)
class_eval      5.680000   0.010000   5.690000 (  5.680143)