![全局上下文
scope chain = [全局对象]
函数上下文
scope chain = 激活对象 + function.[[scope]]
eval上下文
scope chain = calling context.scope chain](https://image.slidesharecdn.com/ecmascript3-130501231437-phpapp01/85/Ecma-script3-25-320.jpg)
![function.[[scope]] =
函数创建时所在EC.scope chain](https://image.slidesharecdn.com/ecmascript3-130501231437-phpapp01/85/Ecma-script3-26-320.jpg)
![1.从作用域链中
取下一个元素
Result(1).[[HasProperty]](Identifier)
No
Yes
base object Result(1)
property name Identifier
Yes
No
base object null
property name Identifier
? 确定当前变量属于作用域链中的哪个
变量对象
? 永远返回Reference](https://image.slidesharecdn.com/ecmascript3-130501231437-phpapp01/85/Ecma-script3-30-320.jpg)
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