js async await

1(async () => {
2  let response = await fetch('/article/promise-chaining/user.json');
3  let user = await response.json();
4  ...
5})();

1// Old School Javascript Invoke
2(async function() {
3	await someAsyncFunction();
4})();
5
6//New ES6 Javascript Invoke
7(async () => {
8	await someAsyncFunction();
9})();

1const data = async ()  => {
2  const got = await fetch('https://jsonplaceholder.typicode.com/todos/1');
3  
4  console.log(await got.json())
5}
6
7data();

1async function showAvatar() {
2
3  // read our JSON
4  let response = await fetch('/article/promise-chaining/user.json');
5  let user = await response.json();
6
7  // read github user
8  let githubResponse = await fetch(`https://api.github.com/users/${user.name}`);
9  let githubUser = await githubResponse.json();
10
11  // show the avatar
12  let img = document.createElement('img');
13  img.src = githubUser.avatar_url;
14  img.className = "promise-avatar-example";
15  document.body.append(img);
16
17  // wait 3 seconds
18  await new Promise((resolve, reject) => setTimeout(resolve, 3000));
19
20  img.remove();
21
22  return githubUser;
23}
24
25showAvatar();

1/* Notes:
2	1. written like synchronous code
3    2. compatible with try/catch blocks
4    3. avoids chaining .then statements
5    4. async functions always return a promise
6    5. function pauses on each await expression
7    6. A non promise value is converted to 
8       Promise.resolve(value) and then resolved
9*/
10
11// Syntax
12// Function Declaration
13async function myFunction(){
14  await ... // some code goes here
15}
16  
17// Arrow Declaration
18const myFunction2 = async () => {
19  await ... // some code goes here
20}
21  
22 // OBJECT METHODS
23
24const obj = {
25	async getName() {
26		return fetch('https://www.example.com');
27	}
28}
29
30// IN A CLASS
31
32class Obj {
33	// getters and setter CANNOT be async
34	async getResource {
35		return fetch('https://www.example.com');
36	}
37}
38  

1console.log("I");
2
3// This will be shown after 2 seconds
4
5setTimeout(()=>{
6  console.log("eat");
7},2000)
8
9console.log("Ice Cream")
10