Method groups

data_structures/unstable_multimap.ts:520–538

* Returns an iterator of `[key, values]` pairs, where `values` is the list * of values associated with that key in insertion order. * * Use this when you need both the key and its full value list, for example * to filter by bucket size. For individual `[key, value]` pairs, use * {@lin

()

   * ```
   */
  groups(): IterableIterator<[K, V[]]> {
    // Hand-rolled for consistency with `entries()` / `values()`. See
    // `entries()` for the rationale. One yield per bucket (no inner loop).
    const outer = this.#map[Symbol.iterator]();
    const iter: IterableIterator<[K, V[]]> = {
      next(): IteratorResult<[K, V[]]> {
        const outerResult = outer.next();
        if (outerResult.done) return { value: undefined, done: true };
        return {
          value: [outerResult.value[0], outerResult.value[1].slice()],
          done: false,
        };
      },
      [Symbol.iterator]() {
        return this;
      },
    };
    return iter;
  }

  /**
   * Returns an iterator of all distinct keys in the map, in insertion order.