Function flipFactory

src/Operations.js:208–243

(collection)

    cacheResultThrough;

export function flipFactory(collection) {
  const flipSequence = makeSequence(collection);
  flipSequence._iter = collection;
  flipSequence.size = collection.size;
  flipSequence.flip = () => collection;
  flipSequence.reverse = function () {
    const reversedSequence = collection.reverse.apply(this); // super.reverse()
    reversedSequence.flip = () => collection.reverse();
    return reversedSequence;
  };
  flipSequence.has = (key) => collection.includes(key);
  flipSequence.includes = (key) => collection.has(key);
  flipSequence.cacheResult = cacheResultThrough;
  flipSequence.__iterateUncached = function (fn, reverse) {
    return collection.__iterate((v, k) => fn(k, v, this) !== false, reverse);
  };
  flipSequence.__iteratorUncached = function (type, reverse) {
    if (type === ITERATE_ENTRIES) {
      const iterator = collection.__iterator(type, reverse);
      return new Iterator(() => {
        const step = iterator.next();
        if (!step.done) {
          const k = step.value[0];
          step.value[0] = step.value[1];
          step.value[1] = k;
        }
        return step;
      });
    }
    return collection.__iterator(
      type === ITERATE_VALUES ? ITERATE_KEYS : ITERATE_VALUES,
      reverse
    );
  };
  return flipSequence;
}

export function mapFactory(collection, mapper, context) {
  const mappedSequence = makeSequence(collection);