Map.js

/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @flow strict
 * @format
 */

// These annotations are copy/pasted from the built-in Flow definitions for
// Native Map.

declare module 'Map' {
  // Use the name "MapPolyfill" so that we don't get confusing error
  // messages about "Using Map instead of Map".
  declare class MapPolyfill<K, V> {
    @@iterator(): Iterator<[K, V]>;
    constructor<Key, Value>(_: void): MapPolyfill<Key, Value>;
    constructor<Key, Value>(_: null): MapPolyfill<Key, Value>;
    constructor<Key, Value>(
      iterable: Iterable<[Key, Value]>,
    ): MapPolyfill<Key, Value>;
    clear(): void;
    delete(key: K): boolean;
    entries(): Iterator<[K, V]>;
    forEach(
      callbackfn: (value: V, index: K, map: MapPolyfill<K, V>) => mixed,
      thisArg?: any,
    ): void;
    get(key: K): V | void;
    has(key: K): boolean;
    keys(): Iterator<K>;
    set(key: K, value: V): MapPolyfill<K, V>;
    size: number;
    values(): Iterator<V>;
  }

  declare module.exports: typeof MapPolyfill;
}