async function giveFive() {
  return 5;
}
async function addAsync(a, b) {
  return a + b;
}
async function chain() {
  var first = await giveFive();
  var second = await addAsync(first, 10);
  return second;
}
var value = await giveFive();
assert(value == 5);
assert(await addAsync(2, 3) == 5);
assert(await chain() == 15);

var promiseValue = giveFive();
assert(!isnull(promiseValue));
assert(await promiseValue == 5);

// Looping with awaits
var total = 0;
for(var i = 0; i < 5; i++) {
  total += await addAsync(i, 1);
}
assert(total == 15);