On Wed, Dec 17, 2008 at 11:05 PM, Ryan Ingram ryani.s...@gmail.com wrote:
...It's possible to extend this idea and generate an arbitrary arbitrary...
Thanks for your thorough answer.
I like the SomeArbitrary idea. I see it's easy to also sample[1] SomeArbitrary.
You do need to add a 'Show'
Hello,
I was playing with the following tree type (attached below) which can
be seen as the reification of an applicative. I wondered if I could
define a QuickCheck Arbitrary instance for it.
The only way I got it to type check however, was to give 'arg' a
monomorphic type (for example: 'Gen
It's absolutely possible. However, I think you do need to enumerate
the possible types somehow.
Here's an example that demonstrates the idea:
{-# LANGUAGE ScopedTypeVariables #-}
sizedTree :: forall a. Arbitrary a = Int - Gen (Tree a)
sizedTree n | n = 0 = liftM Val arbitrary
sizedTree n =
