chess-nlp

A JavaScript library for converting natural language descriptions of chess moves to algebraic notation and vice versa. For example, "bishop takes a8" becomes "Bxa8".

Installation

npm install chess-nlp

Node.js usage

const ChessNLP = require('chess-nlp');

const parser = new ChessNLP();
console.log(parser.textToSan('castle queenside')); // O-O-O
console.log(parser.sanToText('Naxe7#')); // knight a captures e7 checkmate

Browser usage

Script tag

<script src="https://unpkg.com/chess-nlp"></script>
<script>
  var parser = new ChessNLP();
  console.log(parser.textToSan('castle queenside')); // O-O-O
  console.log(parser.sanToText('Naxe7#')); // knight a captures e7 checkmate
</script>

Webpack

import ChessNLP from 'chess-nlp';

const parser = new ChessNLP();
console.log(parser.textToSan('castle queenside')); // O-O-O
console.log(parser.sanToText('Naxe7#')); // knight a captures e7 checkmate

Configuration

The parser can be configured to accept alternate spellings of pieces, ranks, and files. For example:

const options = {
    aliases: {
        knight: ['horse', 'jumper'],
        rook: ['tower'],
        a: ['alpha'],
        b: ['beta', 'bravo'],
        c: ['charlie'],
        1: ['i'],
        2: ['ii'],
        3: ['iii']
    }
};
const parser = new ChessNLP(options);

parser.textToSan('Horse to F6');              // Nf6
parser.textToSan('tower takes b2 checkmate'); // Rxb2#
parser.textToSan('tower alpha takes bravo7'); // Raxb7
parser.textToSan('horse charlie to Alpha 4'); // Nca4
parser.textToSan('tower to betaIII');         // Rb3

The aliases object can contain the following keys:

• king
• queen
• rook
• bishop
• knight
• a
• b
• c
• d
• e
• f
• g
• h
• 1
• 2
• 3
• 4
• 5
• 6
• 7
• 8

Methods

textToSan(text)

toSAN(text)

Convert text to standard algebraic notation. Throws an exception if the text isn't a valid chess move.

parser.textToSan('foo'); // Invalid move: foo

Examples

bishop to D7                    -> Bd7
rook A1                         -> Ra1
queen captures H8               -> Qxh8
king takes F5                   -> Kxf5
knight a to B4                  -> Nab4
Bishop 2 h8                     -> B2h8
Queen C2D3                      -> Qc2d3
queen c 2 d 3                   -> Qc2d3
F captures G4 en passant        -> fxg3
a takes b5 en passant           -> axb6
E5                              -> e5
h take G6                       -> hxg6
c8 promote to Queen             -> c8=Q
F captures E8 promote to knight -> fxe8=N
rook takes b7 mate              -> Rxb7#
Bishop A c3 check               -> Bac3+
E7 check                        -> e7+
castle kingside                 -> O-O
castle Queenside                -> O-O-O
Black Resigns                   -> 1-0
white resigns                   -> 0-1
king to d seven                 -> Kd7

sanToText(san)

fromSAN(san)

Convert san to a natural language description. Throws an exception if the text isn't a valid chess move.

parser.sanToText('bar'); // Invalid move: bar

Examples

e4      -> e4
hxg2    -> h captures g2
axb8=Q  -> a captures b8 promote to queen
cxd1=Q+ -> c captures d1 promote to queen check
d8=Q#   -> d8 promote to queen checkmate
f1=N    -> f1 promote to knight
Kg2     -> king to g2
Qh7     -> queen to h7
Rab7    -> rook a to b7
Bc4     -> bishop to c4
N6e7    -> knight 6 to e7
O-O     -> castle kingside
O-O-O   -> castle queenside
0-1     -> black wins
1-0     -> white wins
1/2-1/2 -> draw

Spanish Translation

Configuration

The parser can be configured to accept spanish translation. Both for SANToText and TextToSAN.

const options = {
    language: 'es'
};
const parser = new ChessNLP(options);

You can combine it with aliases :

const options = {
    aliases: {
        queen: ['reina']
    },
    language: 'es'
};
const parser = new ChessNLP(options);

TextToSAN / ToSAN - Spanish Examples

Alfil D7                        -> Bd7
Torre A1                        -> Ra1
Dama por h8                     -> Qxh8
rey por F5                      -> Kxf5
Caballo a b4                    -> Nab4
alfil 2 h8                      -> B2h8
Dama C2D3                       -> Qc2d3
F por G4 al paso                -> fxg3
a come b5 al paso               -> axb6
E5                              -> e5
h captura G6                    -> hxg6
c8 promociona dama              -> c8=Q
c8 corona dama                  -> c8=Q
c8 igual dama                   -> c8=Q
f por E8 corona caballo         -> fxe8=N
torre por b7 mate               -> Rxb7#
alfil a c3 jaque                -> Bac3+
e7 jaque                        -> e7+
enroque                         -> O-O
enroque corto                   -> O-O
enroque largo                   -> O-O-O
negras abandonan                -> 1-0
blancas abandonan               -> 0-1
rey d siete                     -> Kd7

sanToText / fromSAN - Spanish Examples

e4      -> e4
hxg2    -> h por g2
axb8=Q  -> a por b8 corona a dama
cxd1=Q+ -> c por d1 corona a dama jaque
d8=Q#   -> d8 corona a dama jaque mate
f1=N    -> f1 corona a caballo
Kg2     -> rey g2
Qh7     -> dama h7
Rab7    -> torre a b7
Bc4     -> alfil c4
N6e7    -> caballo 6 e7
O-O     -> enroque corto
O-O-O   -> enroque largo
0-1     -> ganan negras
1-0     -> ganan blancas
1/2-1/2 -> tablas

Contributors

Thanks goes to these wonderful people (emoji key):

This project follows the all-contributors specification. Contributions of any kind welcome!