require 'benchmark'

# Benchmarks for variations of hash operations.
#
#                           user     system      total        real
# each_pair             1.670000   0.000000   1.670000 (  1.685259)
# each_key              0.540000   0.010000   0.550000 (  0.540336)
# each_value            0.530000   0.000000   0.530000 (  0.538994)
# keys.each             0.690000   0.000000   0.690000 (  0.695365)
# values.each           0.690000   0.000000   0.690000 (  0.695188)
#
Benchmark.bm(20) do |x|

  n = 100000
  hash = {}
  ('a'..'z').to_a.each do |letter|
    hash[letter] = letter.upcase
  end

  x.report "each_pair" do
    n.times { hash.each_pair {|key, value|} }
  end

  x.report "each_key" do
    n.times { hash.each_key {|key|} }
  end

  x.report "each_value" do
    n.times { hash.each_value {|value|} }
  end

  x.report "keys.each" do
    n.times { hash.keys.each {|key|} }
  end

  x.report "values.each" do
    n.times { hash.values.each {|value|} }
  end

end