[Haskell] QuickCheck typeclass properties was Re: MonadPlus

Shae Matijs Erisson shae at ScannedInAvian.com
Sat Apr 30 12:59:06 EDT 2005

Jan-Willem Maessen <jmaessen at alum.mit.edu> writes:

>> PS: your discussion of the laws of MonadPlus reinforces to me the real need
>> for being able to declare the laws that a typeclass should satisfy, not just
>> the signature.
> On this I cannot but agree.  But we don't usually count on being able to prove these by construction.

Still, including QuickCheck tests for typeclass laws would be nice.
For example, QuickCheck.Utils has isAssociative, isCommutable, isTotalOrder.
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