@livelybone/singleton

A util of singleton wrapping

Usage no npm install needed!

<script type="module">
  import livelyboneSingleton from 'https://cdn.skypack.dev/@livelybone/singleton';
</script>

README

@livelybone/singleton

NPM Version Download Month gzip with dependencies: 1kb typescript pkg.module

pkg.module supported, which means that you can apply tree-shaking in you project

A util of singleton wrapping

repository

https://github.com/livelybone/singleton.git

Demo

https://github.com/livelybone/singleton#readme

Installation

npm i -S @livelybone/singleton

Global name

Singleton

Usage

import * as Singleton from '@livelybone/singleton'

Use in html, see what your can use in CDN: unpkg

<-- use what you want -->
<script src="https://unpkg.com/@livelybone/singleton/lib/umd/<--module-->.js"></script>

Interface

declare type Fn<T = any> = () => T
/**
 * 每个单例的 id
 *
 * The id of a singleton
 * */
declare type ID = string | number

interface PromiseOnPendingOptions {
  id?: ID
  /**
   * 用于延迟 Promise 实例删除,
   * 如果为 undefined,则在 promise 状态改变之后立即删除
   *
   * Used to delay the deletion of Promise instance,
   * if it is undefined, the promise will be deleted immediately after the state changed
   * */
  delayTime?: number
}

/**
 * @desc 返回 id 对应的一个对象
 *
 *       Return a singleton of any object(such as Promise, Function, Object...) corresponding to the id
 * */
declare function singletonObj<T = {}>(id: ID, defaultValue?: () => T): T

/**
 * @desc 保证一个 id 对应的 promise 在同一时间只存在一个,
 *       并且生成 promise 的函数在 promise pending 状态的时间段内只执行一次,
 *       这个方法可以用来减少同一时间的多余请求
 *
 *       Ensure that only one promise corresponding to the id exists at the same time,
 *       and the function that generates the promise executes only once
 *       during the period of promise pending.
 *       This method can be used to reduce redundant requests at the same time
 * */
declare function promiseOnPending<T = any>(
  proFn: () => Promise<T>,
  options: PromiseOnPendingOptions,
): Promise<T>

/**
 * @desc 封装 setInterval 函数,
 *       保证同一个 id 对应的计时器只有一个在运行,
 *       并且返回一个清除计时器的函数,方便随时终止计时器
 *
 *       A wrapper of the setInterval function,
 *       make sure only one timer for the same id is running,
 *       and returns a function to clear the timer so it can be terminated at any time
 * */
declare function runInterval(id: ID, createFn: Fn): () => void

/**
 * @desc 保证传入的函数在程序的运行期间只运行一次
 *
 *       Ensure that the incoming function runs only once during the run time of the program
 * */
declare function onceRun(fn: Fn, id?: any): void

export { onceRun, promiseOnPending, runInterval, singletonObj }