Generator.prototype.next()

generatorObject.next(value);

function* gen() {
  yield 1;
  yield 2;
  yield 3;
}

const g = gen(); // "Generator { }"
g.next(); // "Object { value: 1, done: false }"
g.next(); // "Object { value: 2, done: false }"
g.next(); // "Object { value: 3, done: false }"
g.next(); // "Object { value: undefined, done: true }"

function* getPage(pageSize = 1, list) {
  let output = [];
  let index = 0;

  while (index < list.length) {
    output = [];
    for (let i = index; i < index + pageSize; i++) {
      if (list[i]) {
        output.push(list[i]);
      }
    }

    yield output;
    index += pageSize;
  }
}

list = [1, 2, 3, 4, 5, 6, 7, 8];
let page = getPage(3, list); // Generator { }

page.next(); // Object {value: (3) [1, 2, 3], done: false}
page.next(); // Object {value: (3) [4, 5, 6], done: false}
page.next(); // Object {value: (2) [7, 8], done: false}
page.next(); // Object {value: undefined, done: true}

function* gen() {
  while (true) {
    let value = yield null;
    console.log(value);
  }
}

const g = gen();
g.next(1);
// "{ value: null, done: false }"
g.next(2);
// 2
// "{ value: null, done: false }"