Types

Here's a list of all commonly used enums

Direction

enum class Direction : int8_t {
    NORTH = 8,
    WEST = -1,
    SOUTH = -8,
    EAST = 1,
    NORTH_EAST = 9,
    NORTH_WEST = 7,
    SOUTH_WEST = -9,
    SOUTH_EAST = -7
};

GameResult

Results are from the current players perspective.

enum class GameResult { WIN, LOSE, DRAW, NONE };

GameResultReason

You have access to this information when calling isGameOver().
NONE simply means that the game is not over yet.

enum class GameResultReason {
    CHECKMATE,
    STALEMATE,
    INSUFFICIENT_MATERIAL,
    FIFTY_MOVE_RULE,
    THREEFOLD_REPETITION,
    NONE
};