[Python-Dev] Re: Decimal type question [Prothon]

[Paul Moore]

Mark Hahn <mark at prothon.org> writes:

> Forgive me if I'm being a pest, but no one has commented on the real reason
> I asked the question.  What does everyone think of the idea of having these
> three built-in numeric types?
>
> 1) An Int implemented with infinite precision integer (Python Longs) with
> the constant/__str__ form of +-NN such as 0, -123, 173_394, etc.
>
> 2) A Decimal implemented with the .Net decimal float (or the IBM decimal if
> the .Net decimal sucks too much) with the constant/__str__ form of +-NN.NN
> such as 0.0, -123.0, 173_394.0, 173394.912786765, etc.
>
> 3) A binary Float implemented with the hardware floating point with the
> constant/__str__ form of +-NN.NN+-eNN such as 0e0, -123e0, 173.39e+3,
> 2.35e-78, etc.
>
> There would be no automatic conversion except the / operator would convert
> from Int to Decimal and the Math module would convert Int and Decimal
> values to Float for almost all functions (except simple ones like abs, min,
> max).

I think that having 2 different fractional types distinguished by
something as subtle as the presence of an exponent (something no other
language does to my knowledge) is an extremely bad idea.

Worse still is the fact that the exponent in the e notation is a
decimal exponent, but the type used is binary!

Paul.
-- 
It is better to be quotable than to be honest -- Tom Stoppard