string_sub_bm.rb

require 'benchmark'

N = 10_000_000

Benchmark.bmbm do |bm|
  bm.report('String') do
    N.times do
      a = 'devise/session'
      a.sub('/', '-')
    end
  end

  bm.report('Regexp') do
    N.times do
      a = 'devise/session'
      a.sub(/\//, '-')
    end
  end

  bm.report('tr') do
    N.times do
      a = 'devise/session'
      a.tr('/', '-')
    end
  end

end