https://github.com/anotherso1a/37Hero/blob/master/chain.js
使用原生JS实现一个英雄类Hero, 可以按照以下方式调用（考察点： JavaScript流程控制）
(1) Hero("37FEer")输出：
Hi!This is 37FEer!
(2) Hero("37FEer").kill(1).recover(30)输出：
Hi!This is 37FEer!
Kill 1 bug (注意：数量1个，所以bug是单数）；
Recover 30 bloods;
(3) Hero("37FEer").sleep(10).kill(2)输出：
Hi!This is 37FEer!
// 等待10秒..
Kill 2 bugs (注意：数量2个，所以bugs是复数)；
function HeroFather(name){
this.name=name
this.task=[]
this.next=function(){
var fn = this.task.shift()
if(fn){
fn()
}
return this
}
//关键步骤，将next方法执行回调
var that=this
setTimeout(function(){
console.log(`Hi, my name is ${that.name}`)
that.next()
})
}
HeroFather.prototype.sleep=function(a){
var that=this
var fn = function(){
var s = a
console.log(`I need sleep ${s}s`)
setTimeout(function(){
that.next()
},s*1000)
}
this.task.push(fn)
return this
}
HeroFather.prototype.kill=function(a){
var that = this
var fn = function(){
var s = a
console.log(`I killed ${s} bug${s>1?'s':''}`);
that.next()
}
this.task.push(fn)
return this
}
HeroFather.prototype.recover=function(a){
var that = this
var fn = function(){
var s = a
console.log(`I recovered ${s} HP`);
that.next()
}
this.task.push(fn)
return this
}
function Hero(name){
return new HeroFather(name)
}
Hero('37FEer')
Hero('37FEer').kill(2).recover(30)
Hero('37FEer').sleep(1).kill(2)
