heather-alexander

Keybase proof

I hereby claim:

• I am heather-alexander on github.
• I am ericadalbassa (https://keybase.io/ericadalbassa) on keybase.
• I have a public key ASBqksDMgae7EwbonvPUx2LEHWvIy6JvduohTLsB7QAnHQo

To claim this, I am signing this object:

heather-alexander

{-# LANGUAGE FunctionalDependencies, FlexibleInstances #-} 

import Data.Maybe (fromJust, isJust)

-- Finite map class suggested in "Type Classes with Functional Dependencies" (Mark Philip Jones, 2000). 

class FiniteMap i e fm  | fm -> i e where
    emptyFM             :: fm
    look                :: i -> fm -> Maybe e
    extend              :: i -> e -> fm -> fm