流れるようなインターフェイス, 引数つき

worker.coffee

class Worker
  constructor: (@context=@)->
    @jobs = []

  register: (job) ->
    @jobs.push job

  work: ->
    job  = do @jobs.shift
    args = [=> @work.apply @, arguments].concat [].slice.call arguments
    job?.apply @context, args

worker = new Worker
worker.register (done, arg)->
  console.log "1 do, arg:#{arg}"
  setTimeout ->
    console.log "1 done"
    done arg + 1
  , 1000

worker.register (done, arg)->
  console.log "2 do, arg:#{arg}"
  setTimeout ->
    console.log "2 done"
    done arg + 1
  , 1000

worker.register (done, arg)->
  console.log "3 do, arg:#{arg}"
  setTimeout ->
    console.log "3 done"
    done arg + 1
  , 1000

worker.work 0