Re: [Haskell-cafe] QuickCheck Arbitrary - infinite recursion on recursive GADTs?

Marc Weber wrote:

data A = A INt | B [A]

instace Arbitrary A where arbitrary = oneof [ liftM A arbitrary , liftM B arbitrary ]

But now QuickCheck will propably create a test value A ( B [ A ( B [ A .... -> no end

Is there an easy QuickCheck way to prevent this?

There are two successive sections in the QuickCheck manual that cover exactly this topic. http://www.cs.chalmers.se/~rjmh/QuickCheck/manual_body.html#15