str_cc_bm.rb

require 'benchmark'
Benchmark.bm(20) do |x|
  x.report ('<<') do
    10_000_000.times do
      one = 'one'
      two = 'two'
      three = 'three'
      y = one << two << three
    end
  end
  x.report ('concat') do
    10_000_000.times do
      one = 'one'
      two = 'two'
      three = 'three'
      y = one.concat(two).concat(three)
    end
  end
 x.report('+') do
    10_000_000.times do
      one = 'one'
      two = 'two'
      three = 'three'
      y = one + two + three
    end
  end
  x.report('#{one}#{two}#{three}') do
    10_000_000.times do
      one = 'one'
      two = 'two'
      three = 'three'
      y = "#{one}#{two}#{three}"
    end
  end
  x.report('one#{two}#{three}') do
    10_000_000.times do
      two = 'two'
      three = 'three'
      y = "one#{two}#{three}"
    end
  end
  x.report('onetwo#{three}') do
    10_000_000.times do
      three = 'three'
      y = "onetwo#{three}"
    end
  end
end