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Game Courier Developer's Guide. Learn how to design and program Chess variants for Game Courier.[All Comments] [Add Comment or Rating]
Fergus Duniho wrote on 2021-10-06 UTC

Is there a way to detect suicide moves in GAME code?

There are two ways of doing a suicide, and these have different effects on the $old variable. Adding an @ to a space works like a promotion, which leaves the value of $old unaffected. Moving a piece nowhere gives $old an empty value. This may give a better indication that the move included a suicide, but it would come at the expense of the information about where the piece moved to.

Since it sounds like your Fire Demon piece is making a multi-part move, you may want to break down the whole move and analyze it step-by-step. You will find examples of this in multi-move variants like Marseillais Chess and Extra Move Chess.

With that in mind, another option would be to move the Fire Demon to the piece's space, then immediately move it back.

Another possibility for detecting a suicide move is to store the board position before the move into a variable, then compare the new position after the move to the stored position and see what differences there are.