Helper to mimic the ES7 spread operation on Objects

ES7ObjectAssignment.js

// Or any object that yields a set of { key: value } pairs.
const x = {
  * [Symbol.iterator] () {
    yield { done: false, value: { dog: 'cat' } }
    yield { done: false, value: { dawg: 'cayt' } }
  }
}

function ES7ObjectAssign (target, source) {
  for (const sourceObject of source) {
    Object.assign (target, sourceObject.value)
  }

  return target
}

console.log (ES7ObjectAssign ({ }, x))