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No Suicide meta rule - Printable Version

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No Suicide meta rule - dale walton - 08-23-2021

I would like a (NoSuicide) Meta rule

In a real game that has opaque move effects,  it functions as a safety net meta rule (preventing the need for take backs on accidental losing moves.)

This potentially would speed up evaluation compared to implementation using ifAfterwards on a move level, as it would integrate with the game evaluation level, rather than the move generation level. To the AI it should be the same as allowing suicides, but filter out branches ending in suicide.

With this Meta rule in place if there were no non-losing moves, and passes are allowed, then the player must pass; or with no non-losing moves and passing is not allowed, then the player would lose without moving.


Note that this Meta rule could be part of Chess:

Meta No Suicide
End if no Moves
Lose if King is Threatened

Implement Castling is a series of moves (or implement special prohibition on Castling through check)

RE: No Suicide meta rule - Eric Piette - 08-23-2021


So to be clear, you would like a meta-rule ludeme to make forbidden the moves in the list of legal moves which are going to make lose the mover if he does that move. Right?


RE: No Suicide meta rule - dale walton - 08-23-2021

Yes, for the human players, to forbid choices that lead to a final state that is a game-losing state.

And maybe to save AI overhead, for the AI's to treat such moves as the lowest priority (worse than just losing) without having to filter them, (except if there is no choice, ending the game before making the move.)

It means the AI prefers losing on the opponent's turn to losing on the players own turn.

RE: No Suicide meta rule - Eric Piette - 08-23-2021


The AI or the humans have exactly the same legal moves. So that's not going to improve or make the game slower. Just make a different game with these moves which becomes forbidden.

But yes, I assume that's possible for me to add that when I have some time. I will check with the others later today to know what they think about it.


RE: No Suicide meta rule - dale walton - 08-23-2021

Would it have potential to improve performance compared to using  (do ifAfterwards:()) to filter each move possibility using a (not + the same condition as the game ending condition?)

In any case it might improve script clarity or make it easy to use in an option.

RE: No Suicide meta rule - dale walton - 08-23-2021

Another approach to how this could work is to have is outside the rules:
With this option, the interface would tell you after you move that "This move is a suicide move, Revert?" before accepting it as your choice.  That more or less fulfills the purpose, but forces the Human/ AI to do the evaluation rather than automatically applying it as a selection rule.

In a game contest with a human player it is granting the right to take-back a losing move before the opponent is notified of the final move choice.

It would probably not be compatible with AI to AI play, but any issue would be very rare. - the answer could default to no take back when AI's play.

In other words make it a GUI option rather than a rule option.