GobanState.elm

module Analysis.GobanState exposing (GobanState, Intersection(..), Stone(..), blank, addStone)

import Matrix exposing (Matrix, repeat, set)

type alias GobanState = Matrix Intersection

type Intersection = Free | Stone
type Stone = Black | White

blank : Int -> GobanState
blank size =
    repeat size size Free

-- addStone : Int -> Int -> Stone -> GobanState -> GobanState Intersection
addStone i j stone goban =
    set i j stone goban

Issue

-- When 

addStone 0 0 Black (blank 3)

-- Type system fails at:
Function `addStone` is expecting the 4th argument to be:

    Matrix.Matrix Stone

But it is:

    GobanState