使用闭包实现每隔一秒打印 1,2,3,4

本节目标：理解“使用闭包实现每隔一秒打印 1,2,3,4”的核心思路，并能把它用于实际开发或面试表达。

 ==使用闭包实现====== ==for== ==(====var== ==i== ===== ==0====; i== ==<== ==5====; i====++====) {======   ==(====function== ==(i) {======     ==setTimeout====(====function====() {======       ==console.====log====(i);======     ==}, i *== ==1000====);======   ==})(i)====== ==}======
==使用== ==let== ==块级作用域======
==for====(====let== ==i== ===== ==0====; i== ==<== ==5====; i====++====){======   ==setTimeout====(====function====() {======     ==console.====log====(i);======   ==}, i *== ==1000====);====== ==}==

> 来自 <https://github.com/CavsZhouyou/Front-End-Interview-Notebook/blob/master/JavaScript/JavaScript.md>