LazyMan实现

const LazyMan = function(name){
  const array = []
  const fn = () => { console.log("Hi! This is "+name+ '!'); next() }
  const next = ()=>{
    const fn = array.shift()
    fn && fn()
  }
  array.push(fn)
  setTimeout(()=>{next()},0)
  const api = {
    sleep: (number) => {
      array.push(()=> {
        setTimeout(()=>{console.log('Wake up after '+ number); next() }, number*1000)
      })
      return api
    },
    eat: (content) => {
      array.push(() => {
        console.log('eat ' + content); next() 
      })
      return api 
    },
    sleepFirst: (number) => { 
      array.unshift(() => {
        setTimeout(()=>{console.log('Wake up after '+5); next() }, number*1000)
      })
      return api
    }
  }
  return api
}