[Haskell-cafe] FiniteMap-like module for unordered keys?

[Remi Turk]

Ugh, replying to myself...
Obviously, the following contains a few mistakes...:

On Wed, Nov 10, 2004 at 11:34:32AM +0100, R. Turk wrote:
> {-# OPTIONS -fglasgow-exts #-}
> {- I want a Hashable instance for String ;) -}
> import Data.FiniteMap
> import Data.HashTable (hashInt, hashString)
> import Data.Int (Int32)
> 
> class Hashable a where hash :: a -> Hash
> instance Hashable Int where hash = hashInt
> instance Hashable String where hash = hashString
> 
> type Hash = Int32
> newtype HashTable a b = HT (FiniteMap Hash [b])
newtype HashTable a b = HT (FiniteMap Hash [(a,b)])

> 
> emptyHT     :: HashTable a b
> emptyHT     = HT emptyFM
> 
> addToHT     :: (Hashable a) => HashTable a b -> a -> b -> HashTable a b
> addToHT (HT m) k v
>             = HT $ addToFM_C (flip (++)) m (hash k) [v]
addToHT (HT m) k v
            = HT $ addToFM_C (flip (++)) m (hash k) [(k,v)]

-- 
Nobody can be exactly like me. Even I have trouble doing it.