HashMap.js

export default class HashMap extends Map {
  delete(key) {
    return super.delete(JSON.stringify(key));
  }

  forEach(callbackFn) {
    super.forEach(([key, value], _, thisArg) =>
      callbackFn(value, key, thisArg)
    );
  }

  get(key) {
    return super.get(JSON.stringify(key))?.[1];
  }

  has(key) {
    return super.has(JSON.stringify(key));
  }

  set(key, value) {
    return super.set(JSON.stringify(key), [key, value]);
  }

  *entries() {
    yield* super.values();
  }

  *keys() {
    for (const [key] of super.values()) {
      yield key;
    }
  }

  *values() {
    for (const [, value] of super.values()) {
      yield value;
    }
  }
}

Object.defineProperties(HashMap.prototype, {
  [Symbol.species]: {
    writable: false,
    enumerable: false,
    configurable: true,
    value: HashMap,
  },
  [Symbol.toStringTag]: {
    writable: false,
    enumerable: false,
    configurable: true,
    value: "HashMap",
  },
});

HashMap.prototype[Symbol.iterator] = HashMap.prototype.entries;