Ranges and the Enum class

[Jim Apple]

On 3/18/06, Aaron Denney <wnoise at ofb.net> wrote:
> Rational _could_ be added here by the diagonal representation, but
> probably sohuldn't.

We could also add an actual enumeration of rationals, as in
http://web.comlab.ox.ac.uk/oucl/work/jeremy.gibbons/publications/rationals.pdf

It would be quite confusing to write, say, [1%2 .. 3%2] and get 2%1
and 1%3 in the middle!

Jim