{- Carrie's Candy Bowl, Code Skeleton (List Representation)
   H. Conrad Cunningham
   
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2018-10-21: Expanded from similar previous work

Notes:

-   In some cases, you may need to restrict the polymorphism to
    implement a function. Be careful not to restrict functions
    unnecessarily.

-   You may find Prelude functions such as concatMap, elem, filter,
    length, map, null, replicate, and span useful.

-   You may also find functions in the Data.List library
    useful -- e.g. sort, group, and (\\).

-}

module CandyBowl_list
  ( CandyBowl(..), newBowl, putIn, takeOut, isEmpty, size, howMany,
    has, eqBowl, inventory, restock, combine, difference, rename
  )
where

-- Used in instructor solution
-- import Data.List ( sort, group, (\\) )

-- Candy bowl data representation
data CandyBowl a = Bowl [a] deriving Show

-- Remove comments from implemented type signatures below

-- Exercise #1
-- newBowl :: CandyBowl a

-- Exercise #2
-- isEmpty :: CandyBowl a -> Bool

-- Exercise #3
-- putIn :: CandyBowl a -> a -> CandyBowl a

-- Exercise #4
-- has :: Eq a => CandyBowl a -> a -> Bool

-- Exercise #5
-- size :: CandyBowl a -> Int

-- Exercise #6
-- howMany :: Eq a => CandyBowl a -> a -> Int

-- Exercise #7
-- takeOut :: (Eq a,Show a) => CandyBowl a -> a -> Maybe (CandyBowl a)

-- Exercise #8
-- eqBowl :: Ord a => CandyBowl a -> CandyBowl a -> Bool

-- Exercise #9                            
-- inventory :: Ord a => CandyBowl a -> [(a,Int)]

-- Exercise #10
-- restock :: [(a,Int)] -> CandyBowl a

-- Exercise #11
-- combine :: CandyBowl a -> CandyBowl a -> CandyBowl a

-- Exercise #12
-- difference :: Eq a => CandyBowl a -> CandyBowl a -> CandyBowl a

-- Exercise #13
-- rename :: CandyBowl a -> (a -> b) -> CandyBowl b