This is a recreation of niklasf's 'python-chess' in C++
All credit for the original code and algorithms go to niklasf and his credits
His source code can be found here: https://github.com/niklasf/python-chess

cpp-chess: a chess library for C++

Introduction

cpp-chess is a chess library for C++, with move generation, move validation, and support for common formats. This is the Scholar's mate in cpp-chess:

    >>> #include "chess.cpp"
    >>> #include <iostream>

    >>> chess::Board board;

    >>> std::cout << board.legal_moves();  // doctest: +ELLIPSIS
    <LegalMoveGenerator at ... (Nh3, Nf3, Nc3, Na3, h3, g3, f3, e3, d3, c3, ...)>
    >>> chess::LegalMoveGenerator legal_moves = board.legal_moves();
    >>> std::cout << (std::find(std::begin(legal_moves), std::end(legal_moves), chess::Move::from_uci("a8a1")) != std::end(legal_moves));
    0

    >>> std::cout << board.push_san("e4");
    Move::from_uci("e2e4")
    >>> std::cout << board.push_san("e5");
    Move::from_uci("e7e5")
    >>> std::cout << board.push_san("Qh5");
    Move::from_uci("d1h5")
    >>> std::cout << board.push_san("Nc6");
    Move::from_uci("b8c6")
    >>> std::cout << board.push_san("Bc4");
    Move::from_uci("f1c4")
    >>> std::cout << board.push_san("Nf6");
    Move::from_uci("g8f6")
    >>> std::cout << board.push_san("Qxf7");
    Move::from_uci("h5f7")

    >>> std::cout << board.is_checkmate();
    1

    >>> std::cout << board;
    Board("r1bqkb1r/pppp1Qpp/2n2n2/4p3/2B1P3/8/PPPP1PPP/RNB1K1NR b KQkq - 0 4")

Features

Supports C++ 20+.

Make and unmake moves.

    >>> chess::Move Nf3 = chess::Move::from_uci("g1f3");
    >>> board.push(Nf3);  // Make the move

    >>> std::cout << board.pop();  // Unmake the last move
    Move::from_uci("g1f3")

Show a simple ASCII board.

    >>> chess::Board board = chess::Board("r1bqkb1r/pppp1Qpp/2n2n2/4p3/2B1P3/8/PPPP1PPP/RNB1K1NR b KQkq - 0 4");
    >>> std::cout << std::string(board);
    r . b q k b . r
    p p p p . Q p p
    . . n . . n . .
    . . . . p . . .
    . . B . P . . .
    . . . . . . . .
    P P P P . P P P
    R N B . K . N R

Detects checkmates, stalemates and draws by insufficient material.

    >>> std::cout << board.is_stalemate();
    0
    >>> std::cout << board.is_insufficient_material();
    0
    >>> std::cout << *board.outcome();
    Outcome(termination=Termination::CHECKMATE, winner=true)

Detects repetitions. Has a half-move clock.

    >>> std::cout << board.can_claim_threefold_repetition();
    0
    >>> std::cout << board.halfmove_clock;
    0
    >>> std::cout << board.can_claim_fifty_moves();
    0
    >>> std::cout << board.can_claim_draw();
    0

With the new rules from July 2014, a game ends as a draw (even without a claim) once a fivefold repetition occurs or if there are 75 moves without a pawn push or capture. Other ways of ending a game take precedence.

    >>> std::cout << board.is_fivefold_repetition();
    0
    >>> std::cout << board.is_seventyfive_moves();
    0

Detects checks and attacks.

    >>> std::cout << board.is_check();
    1
    >>> std::cout << board.is_attacked_by(chess::WHITE, chess::E8);
    1

    >>> chess::SquareSet attackers = board.attackers(chess::WHITE, chess::F3);
    >>> std::cout << attackers;
    SquareSet(0x0000'0000'0000'4040)
    >>> std::cout << (std::find(std::begin(attackers), std::end(attackers), chess::G2) != std::end(attackers));
    1
    >>> std::cout << std::string(attackers);
    . . . . . . . .
    . . . . . . . .
    . . . . . . . .
    . . . . . . . .
    . . . . . . . .
    . . . . . . . .
    . . . . . . 1 .
    . . . . . . 1 .

Parses and creates SAN representation of moves.

    >>> chess::Board board;
    >>> std::cout << board.san(chess::Move(chess::E2, chess::E4));
    e4
    >>> std::cout << board.parse_san("Nf3");
    Move::from_uci("g1f3")
    >>> std::cout << board.variation_san({chess::Move::from_uci("e2e4"), chess::Move::from_uci("e7e5"), chess::Move::from_uci("g1f3")});
    1. e4 e5 2. Nf3

Parses and creates FENs, extended FENs and Shredder FENs.

    >>> std::cout << board.fen();
    rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
    >>> std::cout << board.shredder_fen();
    rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w HAha - 0 1
    >>> chess::Board board = chess::Board("8/8/8/2k5/4K3/8/8/8 w - - 4 45");
    >>> std::cout << board.piece_at(chess::C5);
    Piece::from_symbol('k')

Parses and creates EPDs.

    >>> chess::Board board;
    >>> std::cout << board.epd(false, "legal", std::nullopt, {{"bm", board.parse_uci("d2d4")}});
    rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - bm d4;

    >>> auto ops = board.set_epd("1k1r4/pp1b1R2/3q2pp/4p3/2B5/4Q3/PPP2B2/2K5 b - - bm Qd1+; id \"BK.01\";");
    >>> std::cout << (std::get<std::vector<chess::Move>>(ops.at("bm")) == std::vector({chess::Move::from_uci("d6d1")}) && std::get<std::string>(ops.at("id")) == "BK.01");
    1

pjpuzzler/cpp-chess

cpp-chess: a chess library for C++

Introduction

Features