Asynchronous object map Javascript/node/coffee-script

stuff.coffee

map = (obj, cb) ->
  out = {}
  todo = Object.keys(obj).length
  check = -> cb out if --todo is 0

  for key, val of obj
    if typeof val is 'function'
      do (key) ->
        t = val (res) ->
          out[key] = res
          check()
        if t?
          out[key] = t
          check()
    else
      out[key] = val
      check()
  return

test =
  taskA: (cb) ->
    cb "Some cool async result"
    return
  taskB: "Some cool sync value"
  taskC: -> "Some other cool sync result"

map test, (res) ->
###
{ 
  taskA: 'Some cool async result',
  taskB: 'Some cool sync value',
  taskC: 'Some other cool sync result' 
}
###