ES6学习笔记1

let命令 1.不存在变量提高 console.log(foo); //undefined var foo = 2; console.log(bar); //Uncaught ReferenceError: bar is not defined let bar = 2; 2.不容许重复声明 let a = 10; var a = 20; //Uncaught SyntaxError: Ident

>>阅读原文<<