Chess

Simple chess library for implementing chess games.

Documentation

type Board = Array Coordinates Square

type Coordinates = (Int, Int)

Coordinate format:

 (rank, file)
 (0,0)          (0,7)
    +---> file
    |
    |
    v
   rank
  (7,0)         (7,7)
 -
   +-------+-------+-------+-------+-------+-------+-------+-------+
 8 | (0,0) | (0,1) | (0,2) | (0,3) | (0,4) | (0,5) | (0,6) | (0,7) |
   +-------+-------+-------+-------+-------+-------+-------+-------+
 7 | (1,0) | (1,1) | (1,2) | (1,3) | (1,4) | (1,5) | (1,6) | (1,7) |
   +-------+-------+-------+-------+-------+-------+-------+-------+
 6 | (2,0) | (2,1) | (2,2) | (2,3) | (2,4) | (2,5) | (2,6) | (2,7) |
   +-------+-------+-------+-------+-------+-------+-------+-------+
 5 | (3,0) | (3,1) | (3,2) | (3,3) | (3,4) | (3,5) | (3,6) | (3,7) |
   +-------+-------+-------+-------+-------+-------+-------+-------+
 4 | (4,0) | (4,1) | (4,2) | (4,3) | (4,4) | (4,5) | (4,6) | (4,7) |
   +-------+-------+-------+-------+-------+-------+-------+-------+
 3 | (5,0) | (5,1) | (5,2) | (5,3) | (5,4) | (5,5) | (5,6) | (5,7) |
   +-------+-------+-------+-------+-------+-------+-------+-------+
 2 | (6,0) | (6,1) | (6,2) | (6,3) | (6,4) | (6,5) | (6,6) | (6,7) |
   +-------+-------+-------+-------+-------+-------+-------+-------+
 1 | (7,0) | (7,1) | (7,2) | (7,3) | (7,4) | (7,5) | (7,6) | (7,7) |
   +-------+-------+-------+-------+-------+-------+-------+-------+
       a       b       c       d       e       f       g       h

data Square

Constructors

Square Piece

Empty

Instances

Eq Square

Show Square

data GameState

Instances

Eq GameState

Show GameState

currentPlayer :: GameState -> Color

data Color

Constructors

White

Black

Instances

Eq Color

Show Color

data Piece

Constructors

Piece Color PieceType

Instances

Eq Piece

Show Piece

data PieceType

Constructors

Pawn

Knight

Bishop

Rook

Queen

King

Instances

Eq PieceType

Show PieceType

board :: GameState -> Board

Current board state in the game

fullMoveNumber :: GameState -> Integer

Full move number. Incremented after black's move.

isCheckmate :: GameState -> Bool

Has the game ended in checkmate

isDraw :: GameState -> Bool

Is the game draw? I.e. is the game stalemate or is the game draw by insufficient material.

isLegalMove

Arguments

:: GameState

-> String

Move in coordinate notation. E.g. e2-e4 or b1-c3

-> Bool

Is the given move legal. The only supported move format at the moment is coordinate notation.

isStalemate :: GameState -> Bool

Has the game ended in stalemate

move

Arguments

:: GameState

-> String

Move in coordinate notation. E.g. e2-e4 or b1-c3

-> Maybe GameState

Make a move. The only supported move format at the moment is coordinate notation.

newGame :: GameState

Get initial game state

pieceAt

Arguments

:: Board

-> String

Square coordinate. E.g. e4

-> Maybe Piece

Get the piece at the given coordinate

winner :: GameState -> Maybe Color

Returns the winner of the game if any