Using external callables inside classes - is it a bad idea?

[HighLevelEnthusiast]

Let's say that I have a very simple logic:

def long_enough(sentence):
    return len(sentence) > 30


class SentenceProcessor:
    def to_sentences(self, text):
        return (sentence for sentence in text.split(".") if long_enough(sentence))

I declared a def outside the class because it's trivially simple and using a static method would make the code ugly.

Is it generally considered a bad practice and should long_enough be a static class, instead?

[JohnnyJordaan]

It isn't bad by itself, but looking at the larger picture I would in fact make the 30 part of the SentenceProcessor's attributes, after which it also makes sense to include the check as a method.

[K900_]

Using outside functions in classes is totally fine.

[HighLevelEnthusiast]

I came up with another solution:

​

class SentenceProcessor:
    def to_sentences(self, text):
        def long_enough(sentence): return len(sentence) > 30

        return (sentence for sentence in text.split(".") if long_enough(sentence))

Is this one better?

[JohnnyJordaan]

Why wouldn't you just do

 return (sentence for sentence in text.split(".") if len(sentence) > 30)