Multipurpose chess package for Go/Golang.
This package provides tools for working with chess games. You can:
- Play games
- Play timed games
- Detect checks, checkmates, and draws (stalemate, threefold, 50 move rule, insufficient material)
- Open, save and filter PGN files or strings
- Open EPD files or strings
- Open and save FENs
- Generate legal moves from any position
- and more
For details you can visit the godoc
If you have your GOPATH set in the (recommended way) then you can use go get:
go get github.com/andrewbackes/chess/<pkg name>
otherwise you can clone the repo.
The opinion of this package is that a chess game is a sequence of chess positions. Each position holds all of the state neccessary for a completely new game to start from it. A position is just a snapshot in time right before a players move. This includes the ability to detect three fold repetition, times left on the clocks, fifty-move rule, etc. This opinion is opposed to the game itself always keeping track of such things.
import (
"fmt"
"github.com/andrewbackes/chess/game"
"github.com/andrewbackes/chess/position"
)
func ExampleFoolsMate() {
// Create a new game:
g := game.New()
// Moves can be created based on source and destination squares:
f3 := position.NewMove(position.F2, position.F3)
g.MakeMove(f3)
// They can also be created by parsing algebraic notation:
e5, _ := g.Position.ParseMove("e5")
g.MakeMove(e5)
// Or by using piece coordinate notation:
g4 := position.Move("g2g4")
g.MakeMove(g4)
// Another example of SAN:
foolsmate, _ := g.Position.ParseMove("Qh4#")
// Making a move also returns the game status:
gamestatus := g.MakeMove(foolsmate)
fmt.Println(gamestatus == game.WhiteCheckmated)
// Output: true
}import (
"fmt"
"github.com/andrewbackes/chess/game"
"github.com/andrewbackes/chess/position"
"time"
)
func ExampleTimedGame() {
forWhite := game.NewTimeControl(5*time.Minute, 40, 0, true)
forBlack := game.NewTimeControl(1*time.Minute, 40, 0, true)
tc := [2]game.TimeControl{forWhite, forBlack}
g := game.NewTimedGame(tc)
g.MakeTimedMove(position.Move("e2e4"), 1*time.Minute)
}import (
"bufio"
"fmt"
"github.com/andrewbackes/chess/game"
"os"
"time"
)
func ExamplePlayTimedGame() {
tc := game.NewTimeControl(40*time.Minute, 40, 0, true)
g := game.NewTimedGame([2]game.TimeControl{tc, tc})
console := bufio.NewReader(os.Stdin)
for g.Status() == game.InProgress {
fmt.Print(g, "\nMove: ")
start := time.Now()
input, _ := console.ReadString('\n')
if move, err := g.Position.ParseMove(input); err == nil {
g.MakeTimedMove(move, time.Since(start))
} else {
fmt.Println("Couldn't understand your move.")
}
}
}import (
"fmt"
"github.com/andrewbackes/chess/pgn"
"os"
)
func ExamplePrintGMGames() {
f, _ := os.Open("myfile.pgn")
defer f.Close()
unfiltered, _ := pgn.Read(f)
filtered := pgn.Filter(unfiltered, pgn.NewTagFilter("WhiteElo>2600"), pgn.NewTagFilter("BlackElo>2600"))
for _, game := range filtered {
fmt.Println(game)
}
}import (
"fmt"
"github.com/andrewbackes/chess/fen"
)
func ExampleSaavedraPositionFEN() {
decoded, _ := fen.Decode("8/8/1KP5/3r4/8/8/8/k7 w - - 0 1")
fmt.Println(decoded)
// Will Output: chess board of the position.
encoded, _ := fen.Encode(decoded)
fmt.Println(encoded)
// Will Output: the inputted FEN
}import (
"fmt"
"github.com/andrewbackes/chess/fen"
"github.com/andrewbackes/chess/game"
)
func ExampleSaavedraPositionMoves() {
game, _ := fen.DecodeToGame("8/8/1KP5/3r4/8/8/8/k7 w - - 0 1")
moves := game.LegalMoves()
fmt.Println(moves)
// Will Output: map[b6b7:{} b6a7:{} c6c7:{} b6a6:{} b6c7:{}]
}