瞬间出现

以下代码中，g1() yield 出去的每个值都会在 g2() 的 next() 方法中返回，就像那些 yield 语句是写在 g2() 里一样。（values yielded by g1() are returned from next() calls just like those which are yielded by g2().）

function* g1() {
    yield 2;
    yield 3;
    yield 4;
}

function* g2() {
    yield 1;
    yield* g1();
    yield 5;
}

let iterator = g2();