这是指javascript的内部函数

Question

var a = function foo(){
    this.confusing = 'hell yeah';
    function boo(){
        this...
    } 
}

In function boo() which call inside of foo() , will this be defined for foo() element?

Answer 1

Inside the boo function, this will reference the boo function object, or "window" if you will. This is similar to the stacking of scopes in python, if you're familiar with that.