streams.js

// { DATA, END, READ_ERROR, ERROR } + { PAUSE, RESUME, ABORT, ERROR, FINISH }

// producer
var producer = {
  read: function (cb) {
    // cb(null, DATA)
    // cb(null, undefined | Stream.END_TOKEN)
    // cb(READ_ERROR, undefined | Stream.END_TOKEN)
  },
  abort: function (message) {
    // consumer specific abort implementation
  },
  // this ERROR is an outside of read() ERROR
  onError: function (listener) {}
}

// consumer
function consumer(producer) {
  // PAUSE is do not call .read()
  // RESUME is call .read() one at a time sequentially
  // ABORT is call .abort(optionalMessage)
  
  // return FINI & ERROR
  return {
    // FINISH
    onFinish: function (listener) {},
    // ERROR
    onError: function (listener) {}
  }
}

// however there is a third thing in play here other then consumer & producer
// It's the author & user of the streams

// if consumer or producer creates an error then it needs to be handled
var result = consumer(producer)
producer.onError(function (err) {
  
})
result.onError(function (err) {
  
})
result.onFinish(function () {
  // consumer is done. 
  // continue doing stuff
})