如何禁用函数调用一段时间

Question

我是Python的新版本，只使用它大约一个月左右，我想在Python 2.7.2上制作文本rpg。因此，对于某些命令，例如挖掘或捕鱼，我希望在使用命令之后有一段时间，他们无法在特定时间段内再次使用该命令。

while True:
command = raw_input("Say something")
if command = "mine":
    print "You found 2 Rocks! etc."

我想这样做只能每1分钟使用一次命令 例。 如果时间尚未结束，则会打印

print "Please wait a moment(%s seconds remaining)" % timeleft

Answer 1

首先，你应该使用Python3。但这取决于你。我的回答使用Python3，但您应该能够轻松转换为Python2。

您可以创建一个字典，其中键是命令，值是上次使用该命令的时间戳。例如：

{{1}}

Answer 2

这个答案使用Python 3.6

您可以使用闭包：在这种情况下，通过使用带有可变默认值的命名参数。存储函数的最后一次，并与再次调用时的当前时间进行比较。如果时差太短，则函数返回而不执行代码。

import time


disable_time = 5


def do_stuff_then_disable_for_a_while(stamp=[time.time()-disable_time]):
    """will disable for disable_time after each successful use"""
    if time.time() - stamp[0] > disable_time:
        stamp[0] = time.time()
        print("doing stuff")

    else:
        print("currently disabled")


if __name__ == '__main__':

    while True:

        do_stuff_then_disable_for_a_while()
        time.sleep(1)

输出：

doing stuff
currently disabled
currently disabled
currently disabled
currently disabled
doing stuff
currently disabled
currently disabled
currently disabled
currently disabled
doing stuff

用作装饰者：

这是一个经常遇到的问题，试图给它一个更通用的解决方案：以下允许修饰一个函数，设置它被禁用的时间：

import time
from functools import wraps


class _Disabled:
    """helper class for a decorator that disables
    a function for some time delay"""

    def __init__(self, disable_duration):
        self.first_call = True
        self.disable_duration = disable_duration
        self.last_called = time.time()

    def __bool__(self):
        """return True if disabled, False otherwise
        Attention: has a side effect with consequences:
        ==>> upon first time called, sets first_called flag to false
        """
        if self.first_call:
            self.first_call = False
            return False

        _disabled = time.time() - self.last_called > self.disable_duration

        if _disabled:
            self.last_called = time.time()
            return False
        return True


def disable_for_a_while_after_called(disable_time=5):
    """Decorator factory that modifies the decorated functions so that
    after execution, they are disabled for some time, before they can run
    again
    """
    def _disable_for_a_while_after_called(f):
        must_not_call_function = _Disabled(disable_time)

        @wraps(f)
        def wrapped(*args):
            if must_not_call_function:
                r = None
            else:
                r = f(*args)
            return r
        return wrapped
    return _disable_for_a_while_after_called

用法示例：

if __name__ == '__main__':

    @disable_for_a_while_after_called()
    def do_stuff():
        return "doing stuff"


    @disable_for_a_while_after_called(disable_time=2)
    def do_other_stuff():
        return "doing other stuff"


    @disable_for_a_while_after_called(disable_time=13)
    def do_infrequent_stuff():
        return "doing infrequent stuff"


    for s in range(100):
        a = do_stuff()
        b = do_other_stuff()
        c = do_infrequent_stuff()
        print(f"{s}: {a if a is not None else ' '*11}, "
              f"{b if b is not None else ' ' * 17}, "
              f"{c if c is not None else ''}")
        time.sleep(1)

输出：

0: doing stuff, doing other stuff, doing infrequent stuff
1:            ,                  , 
2:            , doing other stuff, 
3:            ,                  , 
4:            , doing other stuff, 
5: doing stuff,                  , 
6:            , doing other stuff, 
7:            ,                  , 
8:            , doing other stuff, 
9:            ,                  , 
10: doing stuff, doing other stuff, 
11:            ,                  , 
12:            , doing other stuff, 
13:            ,                  , doing infrequent stuff
14:            , doing other stuff, 
15: doing stuff,                  , 
16:            , doing other stuff, 
17:            ,                  , 
18:            , doing other stuff, 
19:            ,                  , 
20: doing stuff, doing other stuff, 
21:            ,                  , 
22:            , doing other stuff, 
23:            ,                  , 
24:            , doing other stuff, 
25: doing stuff,                  , 
26:            , doing other stuff, doing infrequent stuff
27:            ,                  , 
28:            , doing other stuff, 
29:            ,                  ,