On Sat, 17 Nov 2007, Ian Lynagh wrote:
Hi all,
This got a warm reception when I mentioned it in http://www.haskell.org/pipermail/haskell-cafe/2007-June/027557.html so I'm formally proposing it now. It's trac #1902: http://hackage.haskell.org/trac/ghc/ticket/1902
Note that this is a divergence from Haskell 98 (but the libraries already have a handful of small divergences, and Haskell' is just around the corner...).
In my opinion, (^) has the wrong type. Just as we have, for example, (!!) :: [a] -> Int -> a genericIndex :: (Integral b) => [a] -> b -> a we should also have (^) :: (Num a) => a -> Int -> a genericPower :: (Num a, Integral b) => a -> b -> a (or some other function name). The same goes for (^^) (genericPower').
I vote for this proposal. In order not to overuse the prime, I propose genericFractionalPower or genericFracPower for (^^). In my code, the exponent is most oftenly 2.