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

[Ian Lynagh]

On Sat, Nov 17, 2007 at 11:45:52AM -0500, Cale Gibbard wrote:
> On 17/11/2007, Ian Lynagh <igloo at earth.li> 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