如何在python中重用功能代码

Question

I have a basic function with following codes:

def func_0():
    codes_segment_a
    codes_segment_b
    codes_segment_c

Many other small functions share the codes with the func_0, but many add some new codes. Take the following function as an example:

def func_x():
    new codes...
    codes_segment_a
    codes_segment_b
    new codes...
    codes_segment_c

The simpliest and most tedicous solution I figure out is to copy and paste the shared codes. But it looks so stupid because I have more then 20 such functions.

I am quit new in python and please give me some suggestions. Detailed explaination or examples are quite preferred. Thanks.

Answer 1

One general approach is to use classes and inheritance. A super-simplified example (but see Classes for how to use classes and inheritance properly):

class Reuse(object):
    def square(self, x):
        return x**2

class Specific(Reuse):
    def times3(self,x):
        return x*3

sp = Specific()
print(sp.times3(4))

12

print(sp.square(4))

16

If you put utility functions in a "top-level" class, and then make new classes that inherit from that one but that contain the specific functions you want, then you only need to make the utility functions once. There's nothing wrong with making very short functions, even 3-4 lines long, because it can improve readability and efficiency.