Chess notation parser

Crate transforms algebraic chess notation into software readable structs and vice versa. Parsed chess notation for each turn is stored within Turn struct.

To parse a certain chess turn, such as d2xe3, store it in form of &str and pass it as an argument into Turn::try_from() function.

Turn is an enum with two elements:

• Castling - a struct which describes castling turn
• Move - a struct which describes every other possible turn

Example for Castling turn

0-0 will be translated to:

Turn::Castling(Castling {
    r#type: CastlingType::Short,
    flags: Flag::NONE,
});

Examples for Move turns

d6 will be translated to:

Turn::Move (Move {
    who: Piece::Pawn,
    dst: Square::D6,
    flags: Flag::NONE,
    src: None,
    promotion: None,
});

d7xe8=B+? will be translated to:

Turn::Move (Move {
    who: Piece::Pawn,
    dst: Square::E8,
    flags: Flag::CHECK | Flag::CAPTURE,
    src: Some(vec![Square::D7]),
    promotion: Some(Piece::Bishop),
});

Nab3# will be translated to:

Turn::Move (Move {
    who: Piece::Knight,
    dst: Square::B3,
    flags: Flag::CHECKMATE,
    src: Some(Square::get_file('a').unwrap()),  // Vector of 'Ax' squares
    promotion: None,
});

Chess notation parser rules

• Square notation should use lowercase alphabetic characters

  • Valid: a1, a2 ... h7, h8.

• Castling notation can be written with both 0 and O

  • Valid example: 0-0-0 or O-O
  • When Castling turn is printed out, it will be printed with 0 notation

• Notation for pieces:

  • K: King
  • Q: Queen
  • R: Rook
  • B: Bishop
  • N: Knight
  • Pawns are indicated by the absence of the letter

• Capture is annotated with a lowercase x character

  • Valid example: Qxd3

• Check is annotated with a + character

  • Valid example: Qd3+

• Checkmate is annotated with a # character

  • Valid example: Qd3#

• Pawn promotion is annoted with = symbol followed by a piece to which pawn is promoted to

  • Pawn promotion is valid only for ranks 8 and 1
  • Valid example: g8=Q

• Comments ??, !!, ?, !, !?, ?! are allowed only at the end of the turn

  • Valid example: a1=B??
  • Invalid example: ??a1=B