python 装饰器

from time import time


def fa(fun):
    def fb(arg):
        print('start2')
        start = time()
        result = fun(arg)
        print(time() - start)
        print('end2')
        return result

    return fb


def fc(fun):
    def fb(arg):
        print('start1')
        result = fun(arg)
        print('end1')
        return result

    return fb


@fc
@fa
def code(arg):
    print('code haha')
    return arg + '__zxl'


# code=fa(code)
print(code('hello'))

输出:

start1
start2
code haha
0.0
end2
end1
hello__zxl

from time import time


def fz(flag=True):
    def fa(fun):
        def fb(*args):
            print('打印日志') if flag else print('不打印日志')
            print('start2')
            start = time()
            result = fun(*args)
            print(time() - start)
            print('end2')
            return result

        return fb

    return fa

@fz(False)
# @fz(True)

# @fz()

def code(*args):
    print(args)
    return sum(args)


print(code(3, 4, 5, 6, 7))

输出:

不打印日志
start2
(3, 4, 5, 6, 7)
0.0
end2
25

is_login = False


def login(type='weixin'):
    def login1(fun):
        def code():

            global is_login
            if not is_login:
                print(type)
                username = input('用户名:')
                password = input('密码:')
                if username == 'zxl' and password == 'zxl':
                    print('登录成功')
                    is_login = True
                    fun()
                else:
                    print('登陆失败')
            else:
                fun()

        return code

    return login1


@login()
def home():
    print('主页')


@login('QQ')
def news():
    print('新闻')


home()
news()