FEN parser

main.go

package main

import (
	"fmt"
	"strconv"
	"strings"
)

func main() {
	fen := "2r3k1/1q1nbppp/r3p3/3pP3/pPpP4/P1Q2N2/2RN1PPP/2R4K"

	rows := strings.SplitN(fen, "/", -1)
	board := [8][]string{}

	for y := 0; y < len(rows); y++ {
		squares := strings.SplitN(rows[y], "", -1)

		for x := 0; x < len(squares); x++ {
			square := squares[x]
			if num, err := strconv.Atoi(square); err == nil {
				for i := 0; i < int(num); i++ {
					board[y] = append(board[y], " ")
				}
			} else {
				board[y] = append(board[y], square)
			}
		}
	}

	for y := 0; y < len(board); y++ {
		fmt.Println(board[y])
	}
}