bcw (12/03/82)
From: Bruce C. Wright @ Duke University Re: Chess bug No, no, no! It is *not* illegal to castle when one or more of the squares between the King and the Rook are under enemy attack; it is only illegal to castle when 1) The King or the Rook has moved previously; 2) The King is in check; 3) There are nonempty squares between the King and the Rook; 4) The King will move over or onto a square which is attacked by an enemy piece. Note that it says nothing about attacks on the Rook or the squares over which the Rook moves - if the chess program disallows castling when the Rook is moving out of/over attacked squares, it is an evident bug in the program. Bruce C. Wright @ Duke University