BishBosh.Component.Zobrist

AUTHOR

Dr. Alistair Ward

DESCRIPTION

• https://www.chessprogramming.org/Zobrist_Hashing.
• Defines the random-numbers required to construct a hash of a chess-position.
• Facilitates the construction of a hash from arbitrary data.

Type-classes

class Hashable1D hashable x where

An interface to which 1-D hashable data can conform.

Methods

listRandoms1D :: hashable x -> Zobrist x y positionHash -> [positionHash]

Instances

Ix x => Hashable1D EnPassantAbscissa x

Defined in BishBosh.State.EnPassantAbscissa

Methods

listRandoms1D :: EnPassantAbscissa x -> Zobrist x y positionHash -> [positionHash]

Eq x => Hashable1D CastleableRooksByLogicalColour x

Get the list of random numbers required to represent the current castling potential.

Defined in BishBosh.State.CastleableRooksByLogicalColour

Methods

listRandoms1D :: CastleableRooksByLogicalColour x -> Zobrist x y positionHash -> [positionHash]

class Hashable2D hashable x y where

An interface to which 2-D hashable data can conform.

Methods

listRandoms2D :: hashable x y -> Zobrist x y positionHash -> [positionHash]

Instances

(Enum x, Enum y, Ord x, Ord y) => Hashable2D MaybePieceByCoordinates x y

Defined in BishBosh.State.MaybePieceByCoordinates

Methods

listRandoms2D :: MaybePieceByCoordinates x y -> Zobrist x y positionHash -> [positionHash]

(Enum x, Enum y, Ord x, Ord y) => Hashable2D CoordinatesByRankByLogicalColour x y

Defined in BishBosh.State.CoordinatesByRankByLogicalColour

Methods

listRandoms2D :: CoordinatesByRankByLogicalColour x y -> Zobrist x y positionHash -> [positionHash]

(Enum x, Enum y, Ord x, Ord y) => Hashable2D Board x y

Defined in BishBosh.State.Board

Methods

listRandoms2D :: Board x y -> Zobrist x y positionHash -> [positionHash]

(Ix x, Enum x, Enum y, Ord y) => Hashable2D Position x y

Defined in BishBosh.State.Position

Methods

listRandoms2D :: Position x y -> Zobrist x y positionHash -> [positionHash]

(Ix x, Enum x, Enum y, Ord y) => Hashable2D Game x y

Defined in BishBosh.Model.Game

Methods

listRandoms2D :: Game x y -> Zobrist x y positionHash -> [positionHash]

Types

Type-synonyms

Data-types

data Zobrist x y positionHash

The random numbers used to generate a hash, which almost uniquely represent a position.

Instances

Foldable (Zobrist x y)

Defined in BishBosh.Component.Zobrist

Methods

fold :: Monoid m => Zobrist x y m -> m

foldMap :: Monoid m => (a -> m) -> Zobrist x y a -> m

foldMap' :: Monoid m => (a -> m) -> Zobrist x y a -> m

foldr :: (a -> b -> b) -> b -> Zobrist x y a -> b

foldr' :: (a -> b -> b) -> b -> Zobrist x y a -> b

foldl :: (b -> a -> b) -> b -> Zobrist x y a -> b

foldl' :: (b -> a -> b) -> b -> Zobrist x y a -> b

foldr1 :: (a -> a -> a) -> Zobrist x y a -> a

foldl1 :: (a -> a -> a) -> Zobrist x y a -> a

toList :: Zobrist x y a -> [a]

null :: Zobrist x y a -> Bool

length :: Zobrist x y a -> Int

elem :: Eq a => a -> Zobrist x y a -> Bool

maximum :: Ord a => Zobrist x y a -> a

minimum :: Ord a => Zobrist x y a -> a

sum :: Num a => Zobrist x y a -> a

product :: Num a => Zobrist x y a -> a

(Enum x, Enum y, Ord y, Show positionHash, Show x, Show y, Ix x) => Show (Zobrist x y positionHash)

Defined in BishBosh.Component.Zobrist

Methods

showsPrec :: Int -> Zobrist x y positionHash -> ShowS

show :: Zobrist x y positionHash -> String

showList :: [Zobrist x y positionHash] -> ShowS

(Ix x, FiniteBits positionHash, Enum x, Enum y, Ord y, Random positionHash) => Default (Zobrist x y positionHash)

Defined in BishBosh.Component.Zobrist

Methods

def :: Zobrist x y positionHash

Constants

Functions

dereferenceRandomByCoordinatesByRankByLogicalColour :: (Enum x, Enum y, Ord x, Ord y) => Index x y -> Zobrist x y positionHash -> positionHash

Dereferences getRandomByCoordinatesByRankByLogicalColour using the specified index.

dereferenceRandomByCastleableRooksXByLogicalColour

Arguments

:: Eq x

=> LogicalColour

-> x

-> Zobrist x y positionHash

-> Maybe positionHash

The existence of a result depends on whether there remain any Rooks which can castle.

Dereferences getRandomByCastleableRooksXByLogicalColour using the specified abscissa.

dereferenceRandomByEnPassantAbscissa :: Ix x => x -> Zobrist x y positionHash -> positionHash

Dereferences getRandomByEnPassantAbscissa using the specified abscissa.

hash2D :: (Bits positionHash, Hashable2D hashable x y) => hashable x y -> Zobrist x y positionHash -> positionHash

Resolve a hashable into a hash.

combine :: Bits positionHash => positionHash -> [positionHash] -> positionHash

Include a list of random numbers in the hash.

Constructors

mkZobrist

Arguments

:: (Ix x, FiniteBits positionHash, Enum x, Enum y, Ord y, RandomGen randomGen, Random positionHash)

=> Maybe Int

The optional minimum acceptable Hamming-distance between any two of the selected random numbers.

-> randomGen

-> Zobrist x y positionHash

Smart constructor.