作业_返回函数

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#1 Created at ... [Delete] [Delete and Lock User]

def createCounter(): def b(): n = 0 while True: n += 1 yield n i = b() def counter(): return next(i) return counter

#2 Created at ... [Delete] [Delete and Lock User]

我思路和你一样：

def createCounter(): def natural_int(): i = 1 while True: yield i i+=1

#it = natural_int()
def counter():
    return next(natural_int())
return counter

可是这样就错了，为啥，全是1

#3 Created at ... [Delete] [Delete and Lock User]

个人理解： return next(natural_int())这里natural_int()只是临时的generator，调用后就会销毁。return next(i)的话i已经在counter()外部定义了，可以一直使用。

#4 Created at ... [Delete] [Delete and Lock User]

原理不懂，但生成器那章有这样一句话 “调用该generator时，首先要生成一个generator对象，然后用next()函数不断获得下一个返回值”

#5 Created at ... [Delete] [Delete and Lock User]

每次调用CreatCounter都会生成一个新的natural_int函数，都是1也就好理解了。最上面的是把生成器赋值给了i，然后再调用i,你的代码是直接调用生成器函数。