Sorry, I didn't mean to answer you in particular. I meant to say that for tuples you could (I think) have an enumeration over them without requiring any component be bounded. An example of type (Integer, Integer) you would have: [(0,0) ..] = [(0,0) (0,1) (1,0) (0,2) (1,1) (2,0) ... ] where the order can be visualized by taking diagonals of a table starting from the upper left: 0 1 2 .. 0 (0,0) (0,1) (0,2) 1 (1,0) (1,1) (1,2) 2 (2,0) (2,1) (2,2) .. Would this also have an uncomputable order type? At least for comparing tuples you'd just: lt :: (Integer,Integer) -> (Integer,Integer) -> Bool (a,b) `lt` (c,d) = let sum1 = (a + b) sum2 = (c + d) in if sum1 == sum2 then a < c else sum1 < sum2 Implementing fromEnum looks like a bit harder problem.. -- Markus Läll On Fri, Mar 4, 2011 at 5:12 AM, Daniel Fischer < daniel.is.fischer@googlemail.com> wrote:
On Friday 04 March 2011 03:24:34, Markus wrote:
What about having the order by diagonals, like:
0 1 3 2 4 5
and have none of the pair be bounded?
I tacitly assumed product order (lexicographic order).