Can なし be used in response to a binary question?

Question

I'm trying to have a program I'm working on translate a report with "Yes" and "No" as possible answers to various yes/no questions (of forms like "Is X equal to Y," "Does A exist for B," etc). While the existing phrase bank properly renders "Yes" as 「はい」, it has "No" stored as 「なし」 rather than the 「いいえ」 I would have expected. I know that a common way to answer a question in the negative is to just say the negative form of the question's verb, but is that what's going on here?

Is いいえ the only appropriate (and sufficiently generic) answer available, or is なし also appropriate?

Answer 1

The pair はい/なし is highly strange to me. はい/いいえ is better.

The possible way to use なし as an answer is where the question is of ～ありますか？ ("do you have ...") form. In this case, あり/なし is also fine.

For example, one may see a question and answer options like below on a health check sheet:

入院したことはありますか？

あり（3ヶ月以内） / あり（1年以内） / あり（それ以上前） / なし

Answer 2

"Is X equal to Y" can be replied with はい and いいえ

"Does A exist for B" can be replied with はい or いいえ, or あり or なし.

あり・なし deals with existence, they can be roughly translated as:

• あり - there is
• なし - there is not

Is いいえ the only appropriate (and sufficiently generic) answer available, or is なし also appropriate?

It depends on the nature of the question; if it deals with existence or not. Just because はい is used does not preclude なし from being able to respond to a question. Even though はい and なし are not a dichotomous pair.