Re: Distributed Computing in Ada

["Jeffrey R. Carter" <spam.jrcarter.not@spam.acm.org>]

Robert A Duff wrote:
> 
> Well, sort of, but not in a practical way.  Ada tasks share memory, and
> there's no way to tell which variables are shared.  "Distributed" means
> no shared memory.

Ada tasks /can/ share memory, but they don't have to. The rendezvous seems like 
it would map nicely to message passing.

> I actually implemented such a system for Ada 83, where tasks could run
> on different computers.  But there were some severe restrictions on
> shared variables.  Terminate alternatives are "interesting" in that
> context.

Yes, there would have to be some mechanism to deal with shared variables; the 
simplest would be simply to outlaw access to non-local variables in tasks if you 
want to run your program on a distributed system.

-- 
Jeff Carter
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