[Haskell-beginners] Can't square zero as a complex number?

[Brent Yorgey]

On Thu, Jul 26, 2012 at 12:08:00PM -0400, Scott N. Walck wrote:
> Hi,
> 
> Is there a reason why I can't use ** to square zero as a complex number?
> 
> Prelude> :m Data.Complex
> Prelude Data.Complex> (0:+0) ** 2
> NaN :+ NaN
> Prelude Data.Complex> (0 :: Complex Double) ** 2
> NaN :+ NaN

It appears that Complex uses the default implementation of (**),
namely,

  x ** y = exp (log x * y)

I have no opinions on whether this is a good idea.  But as someone
else noted, (^) works fine if you know you want to use a positive
integral power.

-Brent