Re: Rational for not making cursor tagged in Containers

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Sat, 28 Apr 2007 21:31:41 -0500, Randy Brukardt wrote:

> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message
> news:zp8f8yxaqal5.xmxbdrzopa73$.dlg@40tude.net...
>> On Fri, 27 Apr 2007 13:37:34 +0200, Markus E Leypold wrote:
> ...
>>> We just have to assume that anybody knows when two
>>> values are equal.
>>
>> And this is supposed to be the definition of?
> 
> It's not quite that bad, but it is close; see 4.5.2(10):
> 
> "For discrete types, the predefined relational operators are defined in
> terms of corresponding mathematical operations on the position numbers of
> the values of the operations."

I.e. they are defined in terms of positions, not values, which works no
longer we have these positions.

> It surely has nothing to do with bit patterns, but rather the mathematical
> meaning of those bit patterns.

Sure, but we cannot compare meanings on a computer, we can bit patterns
representing meanings. Assuming that different patterns correspond to
different meanings (=injective mapping of), we could compare patterns as if
they were meanings.

> "Value" is one of the concepts that the RM does not try to define (which
> doesn't help this discussion), although it uses the term a lot.

We should not blame RM for that. I guess value is just a narrower word for
meaning. So it just cannot be defined.

> In such a
> case, it is supposed to have the conventional meaning associated with the
> term in English - so I don't think it is possible to completely settle
> this... ;-)

Ah, but what about making cursors tagged? (:-))

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de