Quickcheck?

[jackfirth]

Would it be worthwhile to use quickcheck to make lens law property checks? This has the advantage of making it much easier to find corner cases that break the lens laws (such as #168), but it requires more tests be written, the CI be configured to support it (it should crank up the number of checked cases to absurd levels), and that the target and view of a lens be formally specified. Additionally quickcheck is experiencing some API instability and doesn't play as nicely with RackUnit and CI as I'd like.