Re: PROPOSAL: Restrict the type of (^), (^^), and add genericPower, genericPower'

On Sat, Nov 17, 2007 at 11:45:52AM -0500, Cale Gibbard wrote:

On 17/11/2007, Ian Lynagh wrote:

...

(^) :: (Num a) => a -> Int -> a genericPower :: (Num a, Integral b) => a -> b -> a

This is a move in the opposite direction from what I'd really like to see. The Int type is usually a premature optimisation, and I usually prefer to work with Integer as much as possible, but this just means more fromIntegral conversions (or the use of the awkwardly named general version).

I would much prefer for length, !!, etc. to have more general types, not less general (with compiler specialisation on Int of course).

This proposal is about making (^) and (^^) consistent with everything else. Making everything use Integer rather than Int is an orthogonal question. Someone could also make a Prelude.Integer module, that exports foo :: ... Integer ... foo = genericFoo for various foo which are specialised to Int in Prelude, and reexports all other functions from Prelude. Getting rid of implicit Prelude imports would help too. Thanks Ian