Array based Game of Life

gistfile1.fs

let initField x y s = 
	match (x,y) with
	| (1,1) | (1, 2) | (1,3) -> true
	| _ -> false 


let valueAt (f:bool[,]) c =
	match c with
	| (x,y) when x < 0 -> false
	| (x,y) when y < 0 -> false
	| (x,y) when x >= Array2D.length1 f -> false
	| (x,y) when y >= Array2D.length2 f -> false
	| (x,y) -> f.[x,y]

let rec countTrue b = 
	match b with
	| true :: tail -> 1 + (countTrue tail)
	| false :: tail -> countTrue tail
	| [] -> 0

let getNeighbours f (x,y) = [ 
	(valueAt f (x-1,y-1)) ; (valueAt f (x,y-1)); (valueAt f (x+1,y-1))
	(valueAt f (x-1,y)) ;                        (valueAt f (x+1,y))
	(valueAt f (x-1,y+1)) ; (valueAt f (x,y+1)); (valueAt f (x+1,y+1))
	]
let aliveNeighbours f (x,y) = countTrue (getNeighbours f (x,y))
let newState cur neigh = 
	match (cur, neigh) with
	| (_, 3) -> true
	| (true, 2) -> true
	| _ -> false
	

let playGod f s (x, y) = newState s (aliveNeighbours f (x,y))

let tick f:bool[,] = Array2D.mapi (fun x y s -> playGod f s (x,y)) f
let boolToChar b =
	match b with
	| true -> '#'
	| false -> ' '

let print f = Array2D.map boolToChar f

let blank:bool[,] = Array2D.zeroCreate 10 10
let field0 = Array2D.mapi initField blank
let field1 = tick field0
let field2 = tick field1
printfn "%A" (print field0)
printfn "%A" (print field1)
printfn "%A" (print field2)