Promises (was: Re: Light-weight monitor implementation?)

Philippe Marschall philippe.marschall at
Fri Nov 4 11:34:33 UTC 2005

> One of the biggest differences is that you can perform computations
> with promises - the result is another promise, etcetera. Only when you
> really really really need to do something acute to the promise you end
> up with, you block waiting for all the work to finish.

IIRC there is no way of a blocking wait for promises in E, because
this against the principles of E and could result in a deadlock. But
there are no deadlocks in E because there's just one thread and no

All you can do is register a callback that gets evaluated when the
promise is fulfilled.

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