[Python-ideas] Yet another sum function (fractions.sum)

[MRAB]

On 21/08/2013 15:19, random832 at fastmail.us wrote:
> On Tue, Aug 20, 2013, at 18:47, Andrew Barnert wrote:
>> So instead of math.sqrt and cmath.sqrt, we just have one function that
>> decides whether sqrt(-1) is 0+1j or an exception based on guessing
>> whether you wanted complex numbers? :)
>
> Why exactly is an exception reasonable? If you don't want complex
> numbers, don't take square roots of negative numbers. If you can't
> handle complex numbers, you'll get an exception down the line anyway.
>
I think a simpler rule might be: if the argument is a float then the
result is a float; if the argument is complex then the result is
complex.

If that's the case, then do we really need to keep them separate,
having math and cmath?