Trait shakmaty::Position[−][src]

pub trait Position: Setup {

Show 23 methods    fn legal_moves(&self) -> MoveList;

    fn castles(&self) -> &Castles;

    fn is_variant_end(&self) -> bool;

    fn has_insufficient_material(&self, color: Color) -> bool;

    fn variant_outcome(&self) -> Option<Outcome>;

    fn play_unchecked(&mut self, m: &Move);

    fn san_candidates(&self, role: Role, to: Square) -> MoveList { ... }

    fn castling_moves(&self, side: CastlingSide) -> MoveList { ... }

    fn en_passant_moves(&self) -> MoveList { ... }

    fn capture_moves(&self) -> MoveList { ... }

    fn promotion_moves(&self) -> MoveList { ... }

    fn is_irreversible(&self, m: &Move) -> bool { ... }

    fn king_attackers(
        &self, 
        square: Square, 
        attacker: Color, 
        occupied: Bitboard
    ) -> Bitboard { ... }

    fn swap_turn(self) -> Result<Self, PositionError<Self>>
    where
        Self: Sized + FromSetup,
    { ... }

    fn is_legal(&self, m: &Move) -> bool { ... }

    fn checkers(&self) -> Bitboard { ... }

    fn is_check(&self) -> bool { ... }

    fn is_checkmate(&self) -> bool { ... }

    fn is_stalemate(&self) -> bool { ... }

    fn is_insufficient_material(&self) -> bool { ... }

    fn is_game_over(&self) -> bool { ... }

    fn outcome(&self) -> Option<Outcome> { ... }

    fn play(self, m: &Move) -> Result<Self, PlayError<Self>>
    where
        Self: Sized,
    { ... }

}
Expand description

A legal chess or chess variant position. See Chess for a concrete implementation. Extends Setup.

Required methods

Generates all legal moves.

Castling paths and unmoved rooks.

Checks if the game is over due to a special variant end condition.

Note that for example stalemate is not considered a variant-specific end condition (is_variant_end() will return false), but it can have a special variant_outcome() in suicide chess.

Tests if a side has insufficient winning material.

Returns false if there is any series of legal moves that allows color to win the game.

The converse is not necessarily true: The position might be locked up such that color can never win the game (even if !color cooperates), or insufficient material might only become apparent after a forced sequence of moves.

The current implementation can be summarized as follows: Looking only at the material configuration, taking into account if bishops are positioned on dark or light squares, but not concrete piece positions, is there a position with the same material configuration where color can win with a series of legal moves. If not, then color has insufficient winning material.

Tests special variant winning, losing and drawing conditions.

Plays a move. It is the callers responsibility to ensure the move is legal.

Panics

Illegal moves can corrupt the state of the position and may (or may not) panic or cause panics on future calls. Consider using Position::play() instead.

Provided methods

Generates a subset of legal moves: All piece moves and drops of type role to the square to, excluding castling moves.

Generates legal castling moves.

Generates en passant moves.

Generates capture moves.

Generate promotion moves.

Tests if a move is irreversible.

In standard chess, pawn moves, captures, moves that destroy castling rights, and moves that cede en-passant are irreversible.

The implementation has false-negatives, because it does not consider forced lines. For example, a checking move that will force the king to lose castling rights is not considered irreversible, only the actual king move is.

Attacks that a king on square would have to deal with.

Swap turns. This is sometimes called “playing a null move”.

Errors

Returns PositionError if swapping turns is not possible (usually due to a check that has to be averted).

Tests a move for legality.

Bitboard of pieces giving check.

Tests if the king is in check.

Tests for checkmate.

Tests for stalemate.

Tests if both sides have insufficient winning material.

Tests if the game is over due to checkmate, stalemate, insufficient material or variant end.

The outcome of the game, or None if the game is not over.

Plays a move.

Errors

Returns a PlayError if the move is not legal.

Implementors