BishBosh.Input.SearchOptions

AUTHOR

Dr. Alistair Ward

DESCRIPTION

Defines configurable options related to the process of searching for the optimal move.

Types

Type-synonyms

type SearchDepth = NMoves

The number of plies to search for the optimal move.

type PreferMovesTowardsCentre = Bool

Whether to prefer moves which progress towards the centre of the board.

type SortOnStandardOpeningMoveFrequency = Bool

Sort moves on the decreasing frequency of occurrence in standard openings.

type HammingDistance = Int

The optional minimum Hamming-distance between the random numbers from which Zobrist-hashes are composed.

type MaybeRetireAfterNMoves = Maybe NMoves

The number of full moves (one for each player) after which to retire killer moves.

type TrapRepeatedPositions = Bool

Whether to short-circuit the fitness-evaluation of positions which have been visited before in the current game.

type MaybeUseTranspositions = Maybe (NMoves, SearchDepth)

The number of full moves (one for each player) after which to retire transpositions & the search-depth beneath which they aren't recorded at all.

type Reader = Reader SearchOptions

Self-documentation.

Data-types

data SearchOptions

Defines options related to searching for a move.

Instances

Eq SearchOptions

Methods

(==) :: SearchOptions -> SearchOptions -> Bool

(/=) :: SearchOptions -> SearchOptions -> Bool

Show SearchOptions

Methods

showsPrec :: Int -> SearchOptions -> ShowS

show :: SearchOptions -> String

showList :: [SearchOptions] -> ShowS

NFData SearchOptions

Methods

rnf :: SearchOptions -> ()

Default SearchOptions

Methods

def :: SearchOptions

XmlPickler SearchOptions

Methods

xpickle :: PU SearchOptions

Constants

tag :: String

Used to qualify XML.

searchDepthTag :: String

Used to qualify XML.

minimumSearchDepth :: SearchDepth

The minimum permissible search-depth.

defaultSearchDepth :: SearchDepth

• The default search-depth.
• CAVEAT: this is rather arbitrary.

Functions

Constructor

mkSearchOptions

Arguments

:: PreferMovesTowardsCentre

-> SortOnStandardOpeningMoveFrequency

-> Maybe CaptureMoveSortAlgorithm

-> Maybe HammingDistance

The optional lower bound on the Hamming-distance between the random numbers used to compose Zobrist hashes from positions.

-> MaybeRetireAfterNMoves

The number of full moves back from the current position, after which to retire killer-moves.

-> TrapRepeatedPositions

-> UsePondering

-> MaybeUseTranspositions

The number of full moves after which to retire transpositions, & the search-depth beneath which transpositions aren't recorded.

-> StandardOpeningOptions

-> SearchDepthByLogicalColour

-> SearchOptions

Smart constructor.

Accessors

getSearchDepth :: SearchOptions -> SearchDepth

Get either player's search-depth, using a default value when none are defined.

maybeRetireTranspositionsAfter :: SearchOptions -> MaybeRetireAfterNMoves

When to retire transpositions.

maybeMinimumTranspositionSearchDepth :: SearchOptions -> Maybe SearchDepth

The search-depth beneath which transpositions aren't recorded.

Mutators

setSearchDepth :: SearchDepth -> Transformation

Mutator.

swapSearchDepth :: Transformation

Swap the logical colour associated with any searchDepth currently assigned.

Predicates

recordKillerMoves :: SearchOptions -> RecordKillerMoves

Whether killer-moves are to be recorded.