这并不是特定于语言的，但我将使用 Python 来解释我的问题。
我的程序有几个几乎独立的函数。命令行参数选择这些函数之一，并提供输入文件名。然后执行函数:
# main.py:
import functions
def main():
filename = sys.argv[1]
function_name = sys.argv[2]
function = getattr(functions, function_name)
result = function(filename)
# do something with result
# function.py contains all the functions:
def function1(filename):
# ...
我觉得我应该使用类而不是函数，所以我将每个函数都包装在一个类中。但是现在每个类看起来都非常愚蠢:它只被实例化一次，它所做的只是执行它的构造函数，这与我的旧函数所做的完全一样。然后我可以调用某个方法来检索返回值:
# new version of main.py:
import classes
def main():
filename = sys.argv[1]
cls_name = sys.argv[2]
cls = getattr(classes, cls_name)
calculation = cls(filename)
result = calculation.result()
# do something with result
# classes.py:
import functions
class Class1:
def __init__(self, filename):
self.result = functions.function1(filename)
def result(self):
return self.result
# functions.py is unchanged
这似乎并不比我有函数的时候好多少。有没有办法让我的代码以更有用的方式面向对象？
请您参考如下方法:
如果您正在编写 Java 或 C#，那么您会将这些函数实现为静态方法。在这些语言中，由于语言的设计，所有方法都必须是类的一部分。在 Python 中，虽然您可以模拟静态方法，但对于此示例完全没有必要这样做。
Python 的创造者 Guido van Rossum 拥有 argued in favour of the use of functions rather than methods .
First of all, I chose len(x) over x.len() for HCI reasons (def __len__() came much later). There are two intertwined reasons actually, both HCI:
(a) For some operations, prefix notation just reads better than postfix — prefix (and infix!) operations have a long tradition in mathematics which likes notations where the visuals help the mathematician thinking about a problem. Compare the easy with which we rewrite a formula like x*(a+b) into x*a + x*b to the clumsiness of doing the same thing using a raw OO notation.
(b) When I read code that says len(x) I know that it is asking for the length of something. This tells me two things: the result is an integer, and the argument is some kind of container. To the contrary, when I read x.len(), I have to already know that x is some kind of container implementing an interface or inheriting from a class that has a standard len(). Witness the confusion we occasionally have when a class that is not implementing a mapping has a get() or keys() method, or something that isn’t a file has a write() method.
Saying the same thing in another way, I see ‘len‘ as a built-in operation. I’d hate to lose that. /…/
虽然这与您的问题没有直接关系，但它确实挑战了有时教条的立场，即方法总是优先于功能。
在我看来，在 Python 中，使用函数是比创建类更好的解决方案。
