先来看以下3段代码 代码如下: var firstName = “Mark”; (function DisplayFirstName() { console.log(firstName); })();//必然输出 Mark var lastName = “Aut”; (function DisplayLastName() { var lastName = “Bru”; console.log(lastName); })();//必然输出 Bru, 本地作用域的优先级高于全局作用域 //那么下面这段代码呢? var lastName = “Aut”; (function DisplayLast