我想創建一個每次調用都遞增的函數
def createCounter():
a = 0
def counter():
a += 1
return a[0]
return counter
這裏會報錯 原因是內部的counter不能調用外部的變量a
可以把a換成list 這樣不會改變變量(或沒有改變變量a的引用) 而是改變了a的index的值
def createCounter():
a = [0]
def counter():
a[0] += 1
return a[0]
return counter
#這裏返回的是counter函數
b=createCounter()
print(b())
print(b())
print(b())
print(b())
print(b())
#/usr/local/bin/python3.7 /Users//www/typhon/test.py
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或者可以利用迭代器yeild
def ge():
n = 1
while True:
yield n
n += 1
g = ge()
print(next(g))
print(next(g))
print(next(g))
print(next(g))