What do I do if the OP answers his/her question, but in doing so destroys the question?

Question

Prompted by this question. The original question is of questionable worth, but isn't something I'd immediately dismiss. The asker then edited it to answer the question, thus destroying the question. But I'd like to generalize this to future questions:

What if someone posts a question, then edits it to effectively destroy the question by replacing it with an answer, and yet the question itself and the edits themselves aren't inherently bad, just misplaced. In a situation like this, what's the appropriate action to take?

• Vote to close? It doesn't really seem to fit the closing options: "duplicate of...", "off-topic because...", "unclear what you're asking", "too broad", or "primarily opinion-based".
• Flag it? As what? It's not spam, or offensive/abusive/hate speech, or a duplicate. The options of "it should be closed for another reason..." and "it is very low quality" seem to be the best of the given options if flagging is to be done.
• Roll back the question to its original state? And then do what with the answer? Post it as an answer? I can't (and really don't want to) take credit for that answer.
• Edit the question to include both the original question and the discovered answer? (i.e. top half of question: original question; bottom half of question: discovered answer) But then no answer is to be "accepted," which is unfortunate; it's nice when answered questions have accepted answers.
• Leave a comment and do nothing more? But then the clutter is left to exist on SO. Certainly I think a comment should be left to help educate the user, but I hate to leave the clutter too.

Answer 1

I almost acted on it but I haven't done any C++ in awhile and I don't know what the Nitrous is so I refrained. However, these are the steps that I think would be appropriate

1. Rollback to the OP because, as you said, it has completely ruined the question
2. Leave a comment for the OP to not do that because it is not appropriate and explain why
3. Also, leave comment to OP that they should post an answer and accept it if it worked for them instead of completely destroying the original question and it's context
4. Vote to close the question as it seems too broad, IMHO

I would also consider pinging the editor of that question because those edits didn't need to be made. That person, through comments, obviously agreed that it shouldn't have been edited to destroy the question so they were, effectively, making useless edits. Just for rep (the first edit anyway) I don't know but it really didn't need to be edited.

Answer 2

Self-answering would be ideal. Leaving it absolutely wouldn't be ideal.

I would:

1. Roll-back until the question looks enough like a real question that could get other sensible answers.
2. Copy the answer out of the rolled-back question, posting it as a community wiki answer. That way you don't get credit for something you didn't do.
3. Leave or upvote a comment encouraging the user to leave a self-answer.
4. Check back in a couple days and delete the community wiki answer if it duplicates the user's presumably-non-community-wiki answer.

That way you don't get rep for their answer, SO stays shaped like SO, there is absolutely an acceptable answer, and the OP has an incentive to fix it. You could even leave a comment/note in your CW answer to prefer the OP's answer if it's posted later, but that bleeds a little bit of "meta" into the answer and is a matter of taste.

(If I'm mistaken, and deleting an answer you've posted that you've marked community wiki is not possible, let me know. A previous copied-from-the-comments community wiki answer I've posted has a delete link, but I don't know how well it works.)

Answer 3

Edit the question to include both the original question and the discovered answer

I agree that it would be best as a self-answer, but this leaves SO in the best state. You can message the OP and tell that the best thing to do is make a self-answer.