来源于：阿贤博客

17行代码了解异步：Promise、await、async、setTimeout

async function one() {
    let time = ()=>{
        return new Promise((resolve, reject) => {
            setTimeout(()=>{
                console.log(1);
                resolve(2);
            }, 1000);
        });
    };
    await time();
    console.log(2);
}
let two = ()=>{
    console.log(3);
}
await one();
two();

来源于：阿贤博客