NOTE: When this conversation is concluded, I will move comments to more appropriate places (Apothecary, XBetza, etc.)
The ‘castling out of check’ case suggests to me another definition again ...
Ofc this is probably horribly inefficient to program
Yes, I'm sorry, this is more complicated than I'm prepared to implement. And I'm concerned people won't sufficiently understand it. Look how hard it has been to even get everyone understanding the current issue, and we are all experienced players of chess variants. H.G. did present another idea which we could call Option 4 - for purposes of check determination when the other side is on the move, the Joker is always considered to move as a King. (Sorry if I'm not understanding that right. But I don't think this will be a popular option.)
I don't think the XBetza definition is ambiguous. It says "all moves of the most-recently moved piece type". 'All' really means 'all', so including double-pushes and e.p. captures.
That means that the Interactive Diagram isn't compliant with other rules of Apothecary. That said, I think that is fine. It is unreasonable to expect a simple "prototype" testing engine like the ID to enforce very nuanced rules exactly for all games. But I do think the question is not as clear as you make it out to be. If you add a Joker to Xinagqi, how does it imitate the King? Is it restricted to the palace? If it is not currently in the palace, can it move? Does it "check" the opponent king across an open file? Only in the palace?
NOTE: When this conversation is concluded, I will move comments to more appropriate places (Apothecary, XBetza, etc.)
Yes, I'm sorry, this is more complicated than I'm prepared to implement. And I'm concerned people won't sufficiently understand it. Look how hard it has been to even get everyone understanding the current issue, and we are all experienced players of chess variants. H.G. did present another idea which we could call Option 4 - for purposes of check determination when the other side is on the move, the Joker is always considered to move as a King. (Sorry if I'm not understanding that right. But I don't think this will be a popular option.)
That means that the Interactive Diagram isn't compliant with other rules of Apothecary. That said, I think that is fine. It is unreasonable to expect a simple "prototype" testing engine like the ID to enforce very nuanced rules exactly for all games. But I do think the question is not as clear as you make it out to be. If you add a Joker to Xinagqi, how does it imitate the King? Is it restricted to the palace? If it is not currently in the palace, can it move? Does it "check" the opponent king across an open file? Only in the palace?