This question, which was just closed, seems appropriate to me. My reasons:
- the asker is trying to learn about functional programming
- when reading an article about FP, the asker wasn't able to understand an example due to a key missing concept
- the intent of the question is to understand the concepts behind implementing an algorithm in FP -- not just getting some code
In short, I think it's an on-topic, valuable question (unless a duplicate exists, although I didn't find one), and I've upvoted it.
Is it an appropriate question? If not, can it be improved to meet Programmers' standards (and how)?