--- class (Eq s, Ord s, Show s) => SearchState s where
--- emptySearchState :: MoveState
--- successors :: MoveState -> BurrowContext (Q.Seq MoveState)
--- estimateCost :: MoveState -> BurrowContext Int
--- isGoal :: MoveState -> BurrowContext Bool
--- entryCost :: MoveState -> BurrowContext Int
-
-
--- instance SearchState Position where
-
--- emptySearchState = Position (V2 0 0)
-