package types type Move struct { StartSquare Coordinate `json:"startSquare"` EndSquare Coordinate `json:"endSquare"` PromotionToPiece *string `json:"promotionToPiece,omitempty"` ColorMoved ChessColor PieceMoved PieceShortName } func (m Move) IsPromotionMove() bool { return m.PromotionToPiece != nil }