Python 2.7,智能调节

这篇文章分为两部分,顶部是根据OP的新信息更新的答案 eatAB() 不允许或无法修改。第二个答案是原始答案,如果您有权修改函数本身,您将如何解决这个问题。

更新的答案(您缺乏修改功能的访问/权限)

因为您没有权限在内部更改函数,但您知道它的签名 eatAB(a=None,b=None) 我们想遵循这个逻辑(从问题开始):

• 如果我们传递的值是真实的(例如。 True ),我们要传递值
• 如果该值不为true,我们希望使用参数的默认值,即 None

这可以使用以下表达式轻松实现:

value if condition else otherValue

当调用函数时使用该函数时,会产生以下结果:

a = False
b = True
eatAB(a if a else None, b if b else None)
# will be the same as calling eatAB(None, True) or eatAB(b=True)

当然,如果a和b的值来自某个条件本身,则可以使用该条件。例如:

eatAB(someValue if "a" in myDictionary else None, someOtherValue if "b" in myDictionary else None)

原始答案(您可以在其中修改功能) :

不知道具体是什么 eatAB() 或者它的确切签名,我可以推荐的最好的是以下内容。我相信你可以根据需要进行调整。

主要思想是将这种逻辑转化为 eatAB() 因为这是函数的责任,而不是调用代码的责任。注释中有解释:

# for parameters a and b to be optional as you have shown, they must have a default value
# While it's standard to use None to denote the parameter is optional, the use case shown in the question has default values where a or b are False - so we will use that here.
def eatAB(a=False, b=False):
    # check if the parameters are truthy (e.g. True), in which case you would have passed them in as shown in the question.
    if a:
        # do some logic here for when a was a truthy value
    if b:
        # do some logic here for when b was a truthy value
    # what exactly the eatAB function I cannot guess, but using this setup you will have the same logic as wanted in the question - without the confusing conditional block each time you call it.

# function can then be called easily, there is no need for checking parameters
eatAB(someValue, someOtherValue)

感谢Chris_Rands提出的改进建议。