Asynchronous JavaScript Tips

To define a synchronous function, you have a few options:

let myFunc = () => {...}

function myFunction(){
...
}

Defining function expressions and arrow functions asynchronously looks somewhat different:

let myFunc = async () => {...}

async function myFunction {
...
}

Understanding await has helped me a lot.

[rv] = await expression;

expression: The promise you're waiting for.

rv: The fulfilled value of the promise.

(You can only use await inside asynchronous functions.)

If you have a promise, this code will fail:

let p1 = Promise.resolve(3);
console.log(p1);

But this code will not.

let p1 = Promise.resolve(3);

let myFunc = async () => {
let resolved = await p1;
console.log(resolved); //3
}

myFunc(); // You also could have used an IIFE

It's also useful (and fun!) to understand promises.