Congrats on sticking with your work Dale. I'm impressed.
On Sun, May 9, 2010 at 6:38 PM, Dale Schumacher <dale.schumac...@gmail.com> wrote: > I've been following with great interest the FoNC developments at VPRI. > I too am very interested in compact, simple and expressive > representations of computer-based solutions. My focus for the last > three years has been on the Actor model of computation . It > seems to me that actors are closer to Alan Kay's original concept of > "objects" than the implementation of objects realized in Smalltalk and > its derivatives. As Alan has said, the emphasis should be on the > messages. In a concurrent environment, the asynchronous messaging of > actors is a much better primitive than the synchronous call-return > messaging typical in today's "object-oriented" languages (including > those based on COLA). In order to explore these ideas, I've developed > an actor-based environment for protoyping. Within this environment > I've implemented; a solution to the same-fringe problem, an > implementation of Joe Armstrong's "Erlang Challenge", a fault-tree > simulation, a dialect of FORTH, two dialects of Scheme, and a > meta-circularly-defined actor language called Humus. > > Humus is a pure actor-based programming language that provides a > foundation for software developers to build reliable concurrent > computer systems. It features a referentially transparent > pure-functional core for defining values. These values become the > messages between (and specify the behavior of) dynamically configured > actors. Actor behaviors are composed of concurrent, rather than > sequential, primitive operations. Actor configurations may also be > composed without affecting their operation. This allows > implementation of systems with high scalability and low latency in > both multi-core and distributed execution environments. The > theoretical foundations of Humus have mathematically rigorous > semantics . Unlike Erlang or Scala, there are no blocking > operations and all expressions are completely free of side-effects. > Mutable state is entirely encapsulated within actors and may be > affected only be sending asynchronous messages. > > Some of the implementation techniques used in both Humus and my > actor-based environment (ABE) were inspired by COLA. OMeta also > provided insight into the design of numerous parsers for the various > languages built in ABE. I haven't implemented OMeta directly, but > believe an implementation is possible. The biggest hurdle to that > implementation is the specification of semantic actions. If I use the > host language (Humus) to specify the semantic actions, then I can't > take advantage of all the useful OMeta "code" written for COLA. It > seems that I would have to implement COLA (Coke) as well. I would > love to find a way to connect my work with that of VPRI, to the extent > that we have shared goals. > >  G. Agha. Actors: A Model of Concurrent Computation in Distributed > Systems. MIT Press, Cambridge, Mass., 1986. >  C. Hewitt. Viewing Control Structures as Patterns of Passing > Messages. Journal of Artificial Intelligence, 8(3):323-364, 1977. >  G. Agha, I. Mason, S. Smith, and C. Talcott. A Foundation for > Actor Computation. Journal of Functional Programming, Vol. 7, No. 1, > January 1997. > > _______________________________________________ > fonc mailing list > email@example.com > http://vpri.org/mailman/listinfo/fonc > _______________________________________________ fonc mailing list firstname.lastname@example.org http://vpri.org/mailman/listinfo/fonc