ES6: Generator

developer.mozilla.org

generator関数とyield構文。

function* greetingGenerator() {
  yield 'Hello';
  yield 'こんにちは';
  yield 'Hola';
}

const g = greetingGenerator();
console.log(g.next().value);
console.log(g.next().value);
console.log(g.next().value);