Re: GCC 4.0 Ada.Containers Cursor danger.

On Wed, 06 Jul 2005 09:50:05 +0200, Georg Bauhaus wrote:

> Dmitry A. Kazakov wrote:
>> On 5 Jul 2005 10:11:10 -0700, Dmitriy Anisimkov wrote:
>>
>>>I would propose to have a Ada.Containers subset without cursors for
>>>safety reasons.
>>
>> Yes, or even to remove them completely.
>>
>> It is not clear to me what the semantics a cursor has.
>
> Then it's best to have a look at AI302 or the new standard,
> and learn what semantics a cursor has, before suggesting
> their removal.
>
> What's the translation of "Was der Bauer nicht kennt,
> das frisst er nicht?"

"All of the containers specify positions using a cursor,
which is similar to an access type in that it designates an element."

So? Is it position or access?

"Each container includes a cursor, which is a reference to an element
within a container. Cursors generally remain valid as long as the container
exists and the element referenced is not deleted."

Here it drifts to: a pointer to some element in the container. And what
does it mean to "generally remain valid"? What could a particularly
*invalid* cursor be?

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

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