@esutils/deferred/src/index.ts

The deferred library implemented in Typescript

/**
 * Copyright (C) 2022 Yonggang Luo <luoyonggang@gmail.com>
 *
 */

export class Deferred<T> {
  private readonly _promise: Promise<T>;

  private _resolve!: (value: T | PromiseLike<T>) => void;

  private _reject!: (reason?: any) => void;

  constructor() {
    this._promise = new Promise<T>((resolve, reject) => {
      this._resolve = resolve;
      this._reject = reject;
    });
  }

  get promise(): Promise<T> {
    return this._promise;
  }

  resolve = (value: T | PromiseLike<T>): void => {
    this._resolve(value);
  };

  reject = (reason?: any): void => {
    this._reject(reason);
  };
}