6 Oct
2009
6 Oct
'09
5:40 p.m.
On Oct 6, 2009, at 3:49 AM, Lennart Augustsson wrote:
But complex numbers are just pairs of numbers. So pairs of numbers can obviously be numbers then.
The basic problem here is that pairs of numbers can be made to fit into the Haskell framework with more than one semantics. For example, historically one use for a pair of floating point numbers was to get twice the precision. You implement the operations for that use very differently from the use as complex numbers. If you *know* what you want each of the operations to mean, go ahead. If you don't know, if you have to define some operation just to satisfy the typeclass requirements, and aren't sure what to do in some case, you probably shouldn't use that typeclass.