mwg API
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    Function parseFen

    • Reads a position in Forsyth-Edwards Notation - the shape puzzles come in.

      Placement, side to move, castling rights and the en passant square are read; the halfmove clock and move number are not (draw claims are out of scope), and both kings must be present or there is nothing to judge.

      Parameters

      • fen: string

      Returns ChessState

      import { parseFen, sq } from '@datamoc/mw_games/board';

      // Scholar's mate position, black to move, every castling right still on the books
      const state = parseFen('r1bqkbnr/pppp1Qpp/2n5/4p3/2B1P3/8/PPPP1PPP/RNB1K1NR b KQkq - 0 4');

      console.log(state.turn); // 'black'
      console.log(state.board[sq('f7')]?.side); // 'white' - the queen that just gave check