手写链式调用

遇到一个有趣的题目，做个笔记

实现一个arrange函数，可以进行时间和工作调度
//[> …]表示调用函数后的打印内容

//arrange(‘William’).execute();
//> William is notified

//arrange(‘William’).do(‘commit’).execute();
//>William is notified
//>Start to commit

//arrange(‘William’).wait(5).do(‘commit’).execute();
//>William is notified
//等待5秒
//>Start to commit

//arrange(‘William’).waitFirst(5).do(‘push’).execute();
//等待5秒
//>William is notifed
//>Start to push

function arrange(){
//此处写代码逻辑
}

可以通过链式调用来实现这个问题。每个方法都返回一个对象，该对象包含当前的状态和一系列要执行的方法

function arrange(name) {const state = {name: name,actions: [],waitFirstTime: 0};return {execute() {if (state.waitFirstTime > 0) {setTimeout(() => this.executeAfterWait(), state.waitFirstTime * 1000);} else {this.executeAfterWait();}},executeAfterWait() {console.log(`${state.name} is notified`);state.actions.forEach(action => {if (action.type === 'wait') {setTimeout(action.fn, action.time * 1000);} else {action.fn();}});},do(task) {state.actions.push({type: 'task',fn: () => console.log(`Start to ${task}`)});return this;},wait(time) {state.actions.push({type: 'wait',time: time,fn: () => console.log(`Waited for ${time} seconds`)});return this;},waitFirst(time) {state.waitFirstTime = time;return this;}};
}// 测试用例
arrange('William').execute();
arrange('William').do('commit').execute();
arrange('William').wait(5).do('commit').execute();
arrange('William').waitFirst(5).do('push').execute();