Python decorators

Python 装饰器强大并且高效，这里我们只需要懂得最基础的用法。 等需要更高阶的用法时，自然会主动学习。

# 装饰器(decorators)
# 这个例子中，beg 装饰 say
# beg 会先调用 say。如果返回的 say_please 为真，beg 会改变返回的字符串。
from functools import wraps


def beg(target_function):
    @wraps(target_function)
    def wrapper(*args, **kwargs):
        msg, say_please = target_function(*args, **kwargs)
        if say_please:
            return "{} {}".format(msg, "Please! I am poor :(")
        return msg

    return wrapper


@beg
def say(say_please=False):
    msg = "Can you buy me a beer?"
    return msg, say_please


print(say())  # Can you buy me a beer?
print(say(say_please=True))  # Can you buy me a beer? Please! I am poor :(

参见 这里