一个ES6的笔试题目，求大神们帮忙看看~

 function Example(name){
            return this.name = name;
        }

        console.log([0,"0",[],{},null].map(i => typeof new Example(i).name));

我运行结果为：["number", "string", "undefined", "undefined", "object"]
为什么会有undefined的呐？