Re: Container libraries

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

On Wed, 26 Feb 2003 19:17:52 +0100, Jano <402450@cepsz.unizar.es>
wrote:

>En el mensaje <x7vznokrp3g.fsf@smaug.pushface.org>, simon@pushface.org 
>dice...
>> 402450@cepsz.unizar.es (Jano) writes:
>> 
>> > My requeriments are, basicly: ordering, finding (both
>> > time-efficient) and multitasking support if possible.
>> 
>> What sort of multi-tasking support would _you_ like, then? (the Booch
>> Components used to have some, but as soon as I tried to actually use
>> it myself in a serious application it was obvious that no simplistic
>> approach to multitasking was ever going to satisfy more than a very
>> few users.
>
>I understand it's a complicated matter. I'd like to have protected 
>versions, but also consistent iterators. I must think if I'd prefer 
>constant snapshots (copy) or simply transparently be unaware if an item 
>is removed-added by another task.

The problem is the level of integrity you want to achieve. The lowest
(and easy) level is to ensure the container data consistency upon
concurrent updates. But already iterators would require a higher level
depending on the semantics of what the container contains. Sometimes
you would like to lock the container during the whole iteration
process to have a consistent view on it. Probably you would like to
share such views between multiple tasks. Maybe you would like to allow
a read access to the container at this time. And so on. I doubt, that
there could be an universal and simple approach here.

>I suppose these kinds of doubts are what made you to leave that part to 
>each user.

---
Regards,
Dmitry Kazakov
www.dmitry-kazakov.de