Re: [Haskell-cafe] [Haskell] [ANN] GenCheck - a generalized property-based testing framework

23 Jun 2012


      On 12-06-23 04:38 AM, José Pedro Magalhães wrote:
...
On Tue, Jun 19, 2012 at 4:04 PM, Jacques Carette mailto:carette@mcmaster.ca> wrote:
User beware: this is gencheck-0.1, there are still a few rough
    edges.  We plan to add a Template Haskell feature to this which
    should make deriving enumerators automatic for version 0.2.
Can you provide me a quick pointer into what methods need to be 
generated automatically?
Sure.  Given a data definition such as
data Zipper a = Zip ![a] ![a] deriving (Eq,Show)
(where the strictness annotations are not relevant), one would want to 
automatically generate

instance Enumerated Zipper where
    enumeration = eMemoize $  eProd Zip (eList A) (eList A)

and for
data BinTree a = BTNode a | BTBr (BinTree a) (BinTree a)

generate
instance Enumerated (BinTree Label) where
   enumeration = eMemoize $ eSum (eNode (BTNode A))
(eProd BTBr eBinTree eBinTree)

Jacques