Getting started with chess

To setup the chess game, following have to be done:

• Create tt::chess::Chessboard object
• Populate it with pieces with tt::chess::Chessboard::fill() funcitons
• Make turns with the tt::chess::Chessboard::makeTurn() function and catch corresponding exceptions on the way from the tt::chess::ex namespace.
• Optionally check for checkmates with tt::chess::King::checkmate() thru King object pointer, or trhu tt::chess::Chessboard::currentKing().

Here is simple example of textual chess game implementation:

#include <tartan/chess.hpp>
#include "tartan/board/exceptions.hpp"
 
#include <iostream>
#include <string>
 
int main() {
    // create Board object
    tt::chess::Chessboard board;
    // fill board with default piece set
    board.fill();
 
    std::string turn;
    tt::Piece::Position from, to;
 
    // print chessboard to screen
    std::cout << board;
 
    while (not board.currentKing()->checkmate()) {
        do { // parse for turn
            std::cout << "Enter valid move: ";
            std::cin.clear();
            std::cin >> turn;
        } while (not std::cin);
 
        try { // check if Positions are correct
            from = tt::Piece::Position(turn.substr(0, 2));
            to = turn.substr(2, 2); // use of implicit converion
        } catch (std::exception& ex) {
            std::cout << "Error: position is invalid: " 
                << ex.what() << "\n";
            continue;
        }
        try { // perform the turn
            board.makeTurn(from, to);
        } catch (tt::ex::tartan& ex) {
            std::cout << "Turn error:\n";
            continue;
        }
 
        std::cout << board;
    }
 
    std::cout << "\nGame finished!\n";
 
    return 0;
}

Here are more complex TUI chess game implementation:

#include <tartan/chess.hpp>
#include "tartan/board/exceptions.hpp"
 
#include <iostream>
#include <string>
 
// clears the screen
void cls(void);
 
// recurses to print the explanatory of the exception it holds
void print_exception(const std::exception& e, int level =  0);
 
int main() {
    // create Board object
    tt::chess::Chessboard board;
    // fill board with default piece set
    board.fill();
 
    std::string turn;
    tt::Piece::Position from, to;
 
    // print chessboard to screen
    std::cout << board;
 
    while (not board.currentKing()->checkmate()) {
        do { // parse for turn
            std::cout << "Enter valid move: ____\b\b\b\b";
            std::cin.clear();
            std::cin >> turn;
        } while (not std::cin);
 
        try { // check if from is correct
            from = tt::Piece::Position(turn.substr(0, 2));
        } catch (std::exception& ex) {
            std::cout << "Error: 'from' position is invalid: " 
                << ex.what() << "\n";
            continue;
        }
 
        try { // check if to is correct
            to = turn.substr(2, 2); // use of implicit converion
        } catch (std::exception& ex) {
            std::cout << "Error: 'to' position is invalid: " 
                << ex.what() << "\n";
            continue;
        }
 
        try { // perform the turn
            board.makeTurn(from, to);
        } catch (tt::ex::tartan& ex) {
            std::cout << "Turn error:\n";
            print_exception(ex);
            continue;
        }
 
        cls(); // clear the screen
        std::cout << board; // and put board on it
    }
 
    // announce that game have finished
    std::cout << "\nGame finished!\n" << 
        (board.currentKing()->color() == tt::Piece::Color::White ?
        "White" : "Black") << " king is under checkmate.\n";
 
    return 0;
}
 
void cls(void) {
    for (int i = 0; i < 100; i++)
        std::cout.put('\n');
}
 
void print_exception(const std::exception& e, int level) {
    std::cerr << std::string(level, ' ') << 
        "exception: " << e.what() << '\n';
    try {
        std::rethrow_if_nested(e);
    } catch(const std::exception& e) {
        print_exception(e, level+1);
    } catch(...) {}
}