Elm - Dictionaries

PlayingWithElmDictionaries.elm

-- instead of using a 2D list or 2D array to represent a game node/board, lets use a Dict instead
-- with Dict unlike List or Array, it's much easier to insert, find, and update values
{--
    repl:
    
    make sure you have no trailing spaces after \.  Also, might need to uses spaces not tab in Sublime text
    
    import Dict
board = Dict.fromList \
    [ \
      ((0,0),'X') \
      ,((0,1),' ') \
      ,((0,2),' ') \
      ,((1,1),'O') \
      ,((1,2),'O') \
      ,((1,3),' ') \
      ,((2,0),' ') \
      ,((2,1),' ') \
      ,((2,3),'X') \
    ]
    
    -- repl output: Dict.fromList [((0,0),'X'),((0,1),' '),((0,2),' '),((1,1),'O'),((1,2),'O'),((1,3),' '),((2,0),' '),((2,1),' '),((2,3),'X')]
    : Dict.Dict ( number, number1 ) Char

--}
empty : Char
empty =
    ' '
board = Dict.fromList
    [ 
      ((0,0), 'X')
      ,((0,1), ' ')
      ,((0,2), ' ')
      ,((1,1), 'O')
      ,((1,2), 'O')
      ,((1,3), ' ')
      ,((2,0), ' ')
      ,((2,1), ' ')
      ,((2,3), 'X')              
    ]

-- gets a list of all keys for open positions on the board
-- returns: [(0,1),(0,2),(1,3),(2,0),(2,1)] : List ( number, number1 )
openPositionCoords = Dict.filter (\k v -> v == ' ') board |> Dict.keys