How to get the owner of an FA2 token on chain

Question

For an FA2 nft contract, how can I get the address of the owner of token_id 0 from inside another contract?

Answer 1

The specification does not enforce an implementation for this. You can only verify if a given address owns the token by calling balance_of callback view. In the case of an NFT, balance 1 would mean that a given address owns that token and a balance of 0 that the address does not own it.

Check this thread for an example on how to do that.