fen A Rust Forsyth-Edwards notation parser with proper error handling. extern crate fen; let fen = "rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1"; let board = fen::BoardState::from_fen(fen).unwrap(); assert_eq!(fen, board.to_fen());