js作用域题目

window.number = 4
var obj = {
	'number': 4,
	'tbl': (function(){
		this.number *= 2;
		console.log(this.number)
		console.log("this == window? " +  (this == window))
		return function(){
			this.number *= 2;
			console.log(" 返回函数  this == window? " +  (this == window))
}
})()
}

var tbl = obj.tbl
tbl();
obj.tbl();