Hi Paul
I think that QuickCheck properties, or at least an abbreviated version of them, should be in the documentation. See my RangedSet library (http://ranged-sets.sourceforge.net/) for an example of the kind of thing I mean. However I have to maintain the correspondence between the actual properties and the Haddock comments manually, which is a pain.
See my FilePath library: http://www-users.cs.york.ac.uk/~ndm/projects/libraries.php For example: http://www-users.cs.york.ac.uk/~ndm/projects/filepath/System-FilePath-Versio... This gives a list of properties, which are automatically extracted from the documentation, and checked using QuickCheck. All the tool is in the repo. If anyone wanted to generalise the code in there, it would be handy! Thanks Neil