keys-vs-null.coffee

ITERATIONS = 10000

measure = (title, o) ->
  table =
    'lodash keys': do -> 
      # lodash keys()
      begin = performance.now()
      for i in [1..ITERATIONS]
         _.keys(o)
      performance.now() - begin
  
    'null': do -> 
      # null shalow test
      begin = performance.now()
      for i in [1..ITERATIONS]
         o?
      performance.now() - begin
  
  
  console.log('With', title, '--')
  console.log("#{k}:", v) for k, v of table


measure('an empty object', {})
measure('a few keys', {a: 1, b: 2, c: 3})

o = {}
o["key-#{i}"] = "value #{i}" for i in [1..1000]
measure('a thousand keys', o)

###
VM1027:2 With an empty object --
VM1027:2 lodash keys: 20.864999999990687
VM1027:2 null: 0.11499999999068677
VM1027:2 With a few keys --
VM1027:2 lodash keys: 7.310000000055879
VM1027:2 null: 0.06999999994877726
VM1027:2 With a thousand keys --
VM1027:2 lodash keys: 897.1599999999162
VM1027:2 null: 0.060000000055879354
###