Benchmarking code.rb

require 'benchmark'
TIMES = 10_000_000
:foo # Anal-retentivity

def thrice_yield
  3.times { yield }
end

def thrice_block &block
  3.times &block
end

def thrice_proc_dot_new
  3.times &Proc.new # Yes, you can do that.
end

print "        " # Prettiness :3

Benchmark.bm do |bm|
  bm.report "   yield" do
    TIMES.times do
      thrice_yield { :foo }
    end
  end
  
  bm.report "   block" do
    TIMES.times do
      thrice_block { :foo }
    end
  end
  
  bm.report "Proc.new" do
    TIMES.times do
      thrice_proc_dot_new { :foo }
    end
  end
end

Result

              user     system      total        real
   yield 16.860000   0.110000  16.970000 ( 18.369037)
   block 40.110000   0.290000  40.400000 ( 43.453339)
Proc.new 37.430000   0.250000  37.680000 ( 40.708240)