JavaScript 红黄绿灯交替实现

用回调的方式执行

const run = (time, color, callback) => {
  setTimeout(() => {
    console.log(color);
    callback && callback();
  }, time);
};

let loop = () =>
  run(1000, 'red', run(2000, 'green', run(3000, 'yellow', loop)));

loop();

后记

我开始写成这样了，知道错在哪儿了吗？

const run = (time, color, callback) => {
  setTimeout(() => {
    console.log(color);
    callback && callback();
  }, time);
};
let loop = run(1000, 'red', run(2000, 'green', run(3000, 'yellow', loop)));