quartz/content/notes/06-async-javascript.md

title	aliases	tags
06-async-javascript		lecture cosc203

Async programming allows you to start a potentially long running task have still be able to interact while it it running

general process

• start the task
• return immediately so other tasks can run
• notify us with result when the task is finished

promises

• an object returned by an async function
• represents the current state of the operation
• when the promise is returned to the caller it not always finished
• the promise object has methods to handle the eventual success or failure of the operation

const fetchPromise = fetch('https://url.url.json')

fetchPromise
	.then((reponse) => {
		return response.json();
	})
	.then((data) => {
		console.log(data[0].name)
	})