The question "Java to C++ converter" has attracted some answers, which IMHO are not answers.

This answer and this answer basically say "it's not possible".

I am a software developer, and I agree that it would be very hard to do. And it would be a massive effort for the company providing such a tool, because they probably must implement the whole class library in C++.

Despite the possibility or impossibility, we see in this answer that someone tried it and thinks that they got far enough to sell that. I haven't tried the product, though.

My question: do we allow "It's impossible" answers? Do we want such answers? Should I upvote or downvote? Flag as non-answer?

  • Very interesting question. Your proposed answer, as well as Franck's answer, both have real merits. I'm going to give this some thought. Dec 31, 2021 at 6:21

3 Answers 3


I think that we should we allow "It's impossible" answers for the following reasons:

  • Such answers are useful to inform the OP and other readers of the difficulty or impossibility to provide a program that satisfies their requirements. Amongst other things, this may allow the OP to refine their requirements to make it more possible. Other answers are welcome to prove wrong by recommending a program.
  • Comments can be removed anytime, and nobody except from the mods or SE employees can access removed comments. Therefore, it would be a waste if a good "It's impossible" answer if posted only as a comment, which may disappear anytime and can't be downvoted if incorrect or accepted if correct.

I don't want such answers. They don't help me. And thus I downvote, because that's exactly what the downvote means: "it is not useful".

When I ask a question, I have a problem and I want to solve it. Someone telling me "it's impossible" is much like a "killer phrase". I've had that often enough in the companies I worked for. And also often enough, when I was not fading away, there was a solution.

Maybe it hasn't been done yet and no software exists - well, I get no answers and that's ok. But we don't know what's possible in the future or whether someone is working on that subject.

IMHO it's better to have such statements as comments, before they will turn into the accepted answer.

  • 1
    Other SE sites accept such answers – at least if they are well founded. I agree that SR is somehow special, and such responses should rather be comments (which is what I usually leave here in such cases). Though if something is clearly impossible ("a software that eats my spinach for me" luckily is not possible, at least not in our lifetimes), I'm undecided (hence only a comment here). I still tend toward comments, but (as folks are used differently from other SE sites) wouldn't downvote such an answer – again, provided it's well founded.
    – Izzy Mod
    Dec 30, 2021 at 13:46
  • 1
    I disagree in that it doesn't helps, even though it's certainly not what you wanted. If the answer is sufficiently justified to conclude that no such program could exists it hints you in that you should look for another way to solve your problem, instead of keep spending time in a dead path.
    – Alejandro
    Dec 30, 2021 at 14:57
  • 1
    If some in the future the software become possible, the OP can always change the accepted answer for a new one. In Stack Overflow at least that happens all the time as new versions and alternatives appear.
    – Alejandro
    Dec 30, 2021 at 14:58
  • @Alejandro IMO, "it's impossible" can send a bad signal, e.g., here. Full disclosure: I've got an answer on this post, but I've seen it in other places.
    – jrh
    Jan 12, 2022 at 22:21

Such answers should be allowed and if there is an explanation why it's impossible such answer can be really useful.

So, some example for a question with an "it's not possible" answer could be: Which software calculates (not brute force) the private key from a public key for some really powerful encryption.

  • 1
    This is an interesting possibility: Allow such answers, but only if they include a clear reason as to why it's impossible. Of course, if the reason is incorrect, the answer will be downvoted. But the answer will still remain, which is valuable, because if one person came to an incorrect conclusion, it's likely others may come to the same erroneous conclusion as well. Jan 22, 2022 at 3:52

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .