PEP 335: Overloadable Boolean Operators - Official Posting
Colin J. Williams
cjw at sympatico.ca
Sat Sep 11 08:12:55 EDT 2004
Gerrit wrote:
> Colin J. Williams wrote:
>
>>I understand that the intent, eventually, is that the basic types become
>>classes.
>>
>>Would making Bool a class permit the achievement of these objectives?
>>
>>If Bool were a class, then subclasses could use __repr__ to provide
>>alternative responses to False/True, such as No/Yes or Fail/OK.
>
>
> No, this has nothing to do with it. The representation is not the issue.
> The issue is that currently, 'a and b' returns either a or b. Suppose we
> have an array A = [a1, b1, c1], B = [a2, b2, c2], A and B will currently
> always return A. However, we may want it to return [a1 and a2, b1 and
> b2, c1 and c2]. That is what this PEP is about.
I misled with my comment about reprsentation.
The basic suggestion I was trying to make is that, with a subclass,
the expression 'A and B' could return almost whatever one wishes.
The use of __repr__ is a secondary benefit.
Colin W.
>
> The lack op ability to subclass bool is something different. I don't
> know why that is.
>
> regards,
> Gerrit.
>
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