Java_async await

async function hi() {
	return 1; 
}

async function foo(){
    await someAsyncFunction(){...}
    await anotherAsyncFunction(){...}
} 

(
  async () => {
  
  }
)()

https://youtu.be/aoQSOZfz3vQ

 

//async&await
//clear style of useing promise

//1.promis
function fetchUser() {
  return new Promise((resolve,reject)=>{
    //do network reqeust in 10 sec...
    resolve('lsm') //lsm 출력
  })
}
const user = fetchUser();
user.then(console.log)
console.log(user) //리턴값 promis 출력 : Promise { 'lsm' }

//2.async =1
async function fetchUser2() {
  //return new Promise((resolve,reject)=>{
    //do network reqeust in 10 sec...
    return 'lsm' //lsm 출력
}
const user2 = fetchUser2();
user2.then(console.log)
console.log(user2) //리턴값 promis 출력 : Promise { 'lsm' }

//3. await
function delay(ms) {
  return new Promise(resolve => setTimeout(resolve,ms))
}

async function getApple() {
  await delay(3000)
  return '000'
}

async function getBanana() {
  await delay(3000)
  return '1111'
} 

//위에것과 완전 같다 !
// function getBanana_long() {
//   return delay(3000)
//   .then(()=>"1111")
// }