Example usage of async functions (ES7)

asyncFunctionsExample.js

function foo(delay) {
	return new Promise(resolve => {
		setTimeout(() => {
			resolve(Math.random())
		}, delay)
	})
}

async function run(delaySeconds) {
	const a = foo(delaySeconds * 1000)
	const b = foo(delaySeconds * 1000)
	const c = foo(delaySeconds * 1000)

	// Waits for 3 calls in parallel
	return {
		a: await a,
		b: await b,
		c: await c
	}
}

console.log('starting!')

run(0.5).then((values) => {
	console.log('0.5 seconds')
	console.log(values)
})

run(1).then((values) => {
	console.log('1 second')
	console.log(values)
})

run(3).then((values) => {
	console.log('3.5 seconds')
	console.log(values)
})

run(5).then((values) => {
	console.log('5 seconds')
	console.log(values)
})

Example output