为什么 Python 不是 lexical scoping？
这似乎背离了现代程序设计语言的一般设计思路。
比如
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回复内容：
这段代码是lexical scoping，静态作用域是指我们可以根据代码文本的位置，确定变量的存在区域。按照python的LEGB（Local，Enclosing，Global，Built-in）规则，当调用inner()时，x实际上是在foo的scope中找到的。inner之所能够访问foo中的x，是因为inner is inside the text of foo，这正是lexical的含义。
Bash是Dynamic Scoping的
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这和scoping没有关系。
C++的lambda就可以选择capture by copy或者capture by reference. 根据之前阅读Python源码的经验(如果记错请指正)，在题主的例子里面，这个inner是一个闭包。闭包在Python里面的实现方式是保存一个通往外部namespace的指针(可以理解成一个dictionary)。
楼主可以参看这个例子
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这分明就是lexical scoping嘛，譬如说等价的C#代码
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第一个例子结果都是一样的，因为变量绑定的是引用而不是值。第二个例子：
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输出感觉当前 x 走的 這個問題很好回答：x是inner函數的環境變量，所以在inner的定義中出現的x其實就是對定義外面的，也就是inner的環境變量的一個引用而已。
函數只有在被調用的時候才會執行，你前面將置為1，後面又改為3，不過是改變了x的引用值而已，相當於給x重新賦值。然後執行inner函數，使用x所對應的值為3，因此答案就是4了。
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