On Mon, 3 Nov 1997, Emmanuel BEUQUE wrote:
> I perhaps wasn't clear but I don't see the relation of this with the
> problem I asked. I fully agree with the mechanism you described above
> concerning synchronous events and links that are triggered immediately. I
> find it very useful and use it very often. But my problem is with the last
> sentence of 53.3, which is IMHO an exception.
Yes, it is an exception. Consider a link that deactivates itself. Should all
the pending actions be removed? I don't think so.
> The mechanism of the link deactivation that is postponed when the target is
> itself, is described only there and seems confusing to me, on an author
> point of view.
> ...
> Imagine you were an author and look at the class definition. Look at
> 13.4.Deactivate. There is absolutely no mention there that, if the target
> is the link itself, the dectivation behaviour is only done when all other
> elementary actions of the link effect has been completed. You only see in
> 13.1.2.LinkEffect that elementary actions are executed in synchronous order.
I agree that the IS is sometimes quite confusing, you have to look in different
places to find the correct information.
> That's why I think there is a contradiction there. I'm curious to know how
> your all engines deal with this particular exception.
Can you provide us with a simple test application, please?
> In my opinion, the last sentence of 53.3 should be removed or replaced by
> what I proposed. It seems to me that there is no problem if the link is
> deactivated during the execution of the linkEffect. This shouldn't shorten
> the execution of the linkEffect action anyway (or give me the reason).
> To handle synchronous events (and their possible link effects), an MHEG-5
> engine already has to manage a kind of queue of elementary actions. I don't
> see any problem to store all elementary actions of the link effect in this
> queue as soon as the link is fired.
>
> Any comment ? Any other opinion ?
No, it should not be removed. I can not see that the standard is broken
here. However, I aggree that the important explanations should be moved
as a note to 13.1.2.
Best regards,
Andreas
-- o _ Andreas Kraft (\_|_) GMD FOKUS, kraft@fokus.gmd.de, +49 30 3463-7232 T> ] [ The sky is the limit