一道有意思的题

function machine(name) {
            if(!(this instanceof machine)){
                return new machine(name)
            }  
            this.name = name
            this.logs = []
            this.logs.push(`start ${name}`)
        }
        machine.defer = function(time){
            const times = time
            return function(){
                console.log(`wait ${times}s`)
                return new Promise((resolve)=>{
                    setTimeout(()=>{resolve()},times*1000)
                })
            }
        }
        machine.prototype.execute = async function(){
            const logs = this.logs
            if(logs.length > 0){
                for(let i=0; i<logs.length; i++){
                    if(typeof(logs[i]) === 'function'){
                        await logs[i]()
                    }else {
                        console.log(logs[i])
                    }
                }
            }
        };
        machine.prototype.do = function(argument){
            this.logs.push(`${this.name} ${argument}s`)
            return this
        };

        machine.prototype.wait = function(item){
            this.logs.push(machine.defer(item))
            return this
        };

        machine.prototype.waitFirst = function(item){
            this.logs.unshift(machine.defer(item))
            return this
        };


        // machine('ygy').execute()
        // start ygy
        // machine('ygy').do('eat').execute(); 
        // start ygy
        // ygy eat
        machine('ygy').wait(1).do('eat').execute();
        // start ygy
        // wait 5s（这里等待了5s）
        // ygy eat
        // machine('ygy').waitFirst(1).do('eat').execute();
        // wait 5s
        // start ygy
        // ygy eat