class DeeplyNestedIterator {
  constructor(nestedList) {
    this.gen = this.listGenerator(nestedList);
    this.nextVal = this.gen.next();
  }

  hasNext() {
    return !this.nextVal.done;
  }

  getNext() {
    const val = this.nextVal.value;
    this.nextVal = this.gen.next();
    return val;
  }

  *listGenerator(list) {
    for (const el of list) {
      if (Array.isArray(el)) yield* this.listGenerator(el);
      else yield el;
    }
  }
}