[racket] Places, Channels as Events. Labeling Places.

On Fri, 14 Dec 2012 07:25:36 +0100, David T. Pierson <dtp at mindstory.com>  
wrote:

> I've wondered about this.  What is the rational behind these
> differences?  Wrapping events is cumbersome.
>
> For instance, my first intuition is that the synchronization result of a
> place channel would be the place channel itself, just like the
> synchronization result of a thread is the thread itself.  Why aren't
> these analogous?

I would guess it prevents race-conditions. Channels and place-channels may  
be accessed from any number of threads, and therefore it would be possible  
that the data on the channel is removed between the sync and the  
*-get-call. Thread channels are different in that it's guaranteed that  
only one thread can access them.
Input-ports for example suffer from these races and the user has to make  
sure to prevent or handle the them correctly.

Tobias



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Tobias Hammer
DLR / Institute of Robotics and Mechatronics
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Mail: tobias.hammer at dlr.de