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thomas-maeder / popeye

Popeye is a chess problem solving and testing software with strong support for fairy chess and heterodox genres. For more information cf. topic "Popeye (chess)" on http://en.wikipedia.org/
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Republican Chess - retract a move to detect some illegal mating positions #29

Open thomas-maeder opened 16 years ago

thomas-maeder commented 16 years ago

In Republican Chess there are initially no kings. If the side which has just moved can insert the opposite king on a square where it would be checkmated, then they may do this. The resultant mate must be legal. Currently, Popeye does not check for legal mating positions, because in general it requires a human brain. However, it should be possible to modify Popeye to remove the vast majority of "solutions" with illegal mating positions. Popeye could test each purported solution by attempting to retract a move (which could include the retraction of a promotion and/or capture), so that the mated side is no longer in check. If such a retraction is not possible then the mating position is illegal.

Original comment by: geofffoster

thomas-maeder commented 11 years ago

Original comment by: thomas-maeder

thomas-maeder commented 10 years ago

Ticket moved from /p/popeye-chess/bugs/34/

Original comment by: thomas-maeder