[Python-Dev] PEP for adding a decimal type to Python
Fri, 27 Jul 2001 16:32:42 -0400
On Friday 27 July 2001 11:50 am, Guido van Rossum wrote:
> I'm not optimistic about Michael's PEP. He seems to insist on a total
> separation between decimal and binary numbers that I don't believe can
I'm not insisting on total separation. I propose that we start with a
requirement that an explicit call be made to a conversion function. These
functions would allow a decimal type to be converted to a float or to an int.
There would also be conversion function going from a float or an int to a
What I would like to avoid is creating a decimal type in Python that enables
silent errors that are difficult to recognize. Allowing automatic coersion
between the binary and decimal types will open the door to errors that would
be detected if a conversion is required. If at some point in the future it
becomes apparent that a particular form of coersion is safe and useful it
could be added. I'd like to move slowly on opening up this potential trouble
> I haven't replied to him yet because I can't explain it well
> enough yet -- but I don't believe there's much of a future in his
> particular idea.
I guess I'm not understanding something about the direction you are taking
Python. As I understood the goals of the CP4E project you were attempting
to make Python appealing to a wider audience and make it possible for
everyone to learn to write programs. And then there are occasional
references to a Python 3k which will fix some Python warts. My proposal
moves Python towards these goals, while retaining full backwards compatible.
I am not trying to create a new interpreter. I'm trying to make the current
interpreter useful to a wider market. What is it you are trying to
accomplish in the process of "unifying the numerical types" in Python?