一道有趣的面试题---while阻断同步进程

需求：

实现一个LazyMan，可以按照以下方式调用:
        1) LazyMan(“Hank”)输出:
           Hi! This is Hank!

        2) LazyMan(“Hank”).sleep(10).eat(“dinner”)输出
           Hi! This is Hank!
           //等待10秒..
           Wake up after 10
           Eat dinner~

        3) LazyMan(“Hank”).eat(“dinner”).eat(“supper”)输出
           Hi This is Hank!
           Eat dinner~
           Eat supper~

        4) LazyMan(“Hank”).sleepFirst(5).eat(“supper”)输出
            //等待5秒
            Wake up after 5
            Hi This is Hank!
            Eat supper*/

实现

function lazyMan(name) {
        function Man() {
            setTimeout(function () {
                console.log(`Hi! This is ${name}!`);
            },0)
        }
        Man.prototype.sleep = function (time) {
            /!*setTimeout(function () {
                console.log(`Wake up after ${time}!`);
            },time*1000);*!/
            // 把异步的转成同步的等待10秒；
            setTimeout(function () {
                // 加定时器，为了让此处整体变成异步；
                let duration = time *1000;// 10秒的毫秒差；
                let curTime= Date.now();
                //当过了10秒之后，继续执行下面的代码;while 循环是用来阻塞当前主线程；因为while循环是同步的；当while不结束；那么代码不能向下运行；
                while(Date.now()-curTime<=duration){};
                console.log(`Wake up after ${time}!`);
            },0);
            return this;
        }
        Man.prototype.eat = function (food) {
            setTimeout(function () {
                console.log(`Eat  ${food}~`);
            },0)
           return this;// 实例
        };
        Man.prototype.sleepFirst = function (time) {
            let  duration = time*1000;
            let curTime =Date.now();
            // while ： 用来阻塞线程；不是只有定时器可以解决时间问题；
            while(Date.now()-curTime<=duration){};
            console.log(`Wake up after ${time}`);
            return this;
        }
        return new Man();
    }
    //lazyMan("hank")
    //lazyMan("Hank").sleep(10).eat("dinner");
    //lazyMan("Hank").eat("dinner").eat("supper")
    lazyMan("Hank").sleepFirst(5).eat("supper");