[Python-Dev] PEP 242 Numeric kinds

Michael McLay mclay@nist.gov
Fri, 6 Dec 2002 11:38:29 -0500


On Friday 06 December 2002 02:12 am, Brett Cannon wrote:
> [Paul F Dubois]
>
> > We had put off consideration of PEP 242 Numeric kinds until June 2002
> > when a meeting of some interested parties was to occur but the meeting
> > didn't occur. 
[...] 
> I just want to be able to add up a bunch of money values and not have a
> few pennies disappear in the end; usually I am the one who has to eat the
> loss and I am an poor college graduate who can't afford the rounding.  =)

Does the kinds implementation work with binary floats and decimal numbers? 
>From a quick scan of the PEP it looks like it is only binary floats. If it 
only applies to binary numbers then the kinds capability will not eliminate 
decimal number rounding errors. That problem will require extending Python to 
include a decimal number type. 

The abstract mentions a clarification of decimal literals, but I suspect Paul 
was not suggesting that the numbers defined by kinds will use decimal 
arithmetic instead of binary arithmetic.