javascript - IE8 `window.fn !== fn`

Question

谁能解释一下？ IE8

( function(){
    window.foo = function foo(){};
    console.log( window.foo === foo ); // false
}() );

Answer 1

由于 IE 错误，命名函数表达式创建了一个单独的本地 foo 变量，其中包含函数的单独副本。

More info :

var f = function g(){};
f === g; // false

This is where things are getting interesting. Or rather — completely nuts. Here we are seeing the dangers of having to deal with two distinct objects — augmenting one of them obviously does not modify the other one; This could be quite troublesome if you decided to employ, say, caching mechanism and store something in a property of f, then tried accessing it as a property of g, thinking that it is the same object you’re working with.