more automatic tests for containers

[Jean-Philippe Bernardy]

> Doctest came from the Python tradition, which is a very imperative outlook
> on life. I wonder whether doctest could be modified to better match the
> programming, documentation, and testing style of Haskell. In particular, I'd
> expect it to recognize "=="-style statements as things to test. The only
> real issue is whether those statements should be considered unit tests or
> properties (testable by QuickCheck and SmallCheck), since those two
> categories have very different methods of being verified.

Isn't a unit test just a property with 0 free variable?
If so, equality statements can always be handled by Quick/SmallCheck.

Cheers,
JP.