Example 6-16. Passing values into the generator

function* counter() {
	var count = 0;
	var increment = 1;
	while (true) {
		count = count + increment;
		increment = (yield count) || increment;
	}
}

var iterator = counter();
console.log(iterator.next().value);   // 1
console.log(iterator.next().value);   // 2
console.log(iterator.next().value);   // 3
console.log(iterator.next(10).value); // 13 <- Start counting by 10
console.log(iterator.next().value);   // 23
console.log(iterator.next().value);   // 33