Module bitboard 

A general purpose way to efficiently encode data, where each bit index of a 64-bit unsigned integer represents a chessboard square.

Data Order:

• Little-Endian Rank-File mapping (LSR)
• A1 = least significant bit = 0b0 = 0
• B1 = 0b1 = 1
• C1 = 0b10 = 2
• A2 = 0b1000 = 8
• H8 = most significant bit = 0x8000000000000000

Compass Rose Bit Shifting:

NoWe       North       NoEa
     +7     +8      +9
West -1      0      +1 East
     -9     -8      -7
SoWe       South       SoEa

Examples of data that may be represented with Bitboards:

• W/B King position
• W/B Queen positions
• W/B Rook positions
• W/B Bishop positions
• W/B Knight positions
• W/B Pawn positions
• Pawn Attack Pattern per square
• Knight Attack Pattern per square
• King Attack Pattern per square
• Sliding Attack Pattern per square
• Pass Pawns

Structs

Bitboard

Bitboard is a wrapper around a u64 integer, where each bit represents some or none on its corresponding chess board square. It is used to encode a set of some arbitrary homogenous data for an entire chess board.

BitboardSquareIterator

Iterator type that yields each square in a bitboard through efficient generation.

Type Aliases

BitboardKind

Alias for inner type of Bitboard. Useful for const evaluation.