python全局变量警告

2019独角兽企业重金招聘Python工程师标准>>>

SyntaxWarning: name 'spam' is assigned to before global declaration

例：

x = 0

def func(a, b, c):
    if a == b:
        global x
        x = 10
    elif b == c:
        global x
        x = 20

If you run this in a recent version of Python, the compiler will issue aSyntaxWarning pointing to the beginning of the func function.

Here’s the right way to write this:

x = 0

def func(a, b, c):
    global x # <- here
    if a == b:
        x = 10
    elif b == c:
        x = 20

修改全局变量在函数改变修改前定义即可

转载于:https://my.oschina.net/yves175/blog/821579