Path: utzoo!attcan!uunet!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!samsung!rex!ames!sun-barr!ccut!s.u-tokyo!rkna50!nttlab!icot32!icot21!chik From: chik@icot.or.jp (Chikayama Takashi) Newsgroups: comp.lang.prolog Subject: Re: OOP vs Logic Programming II Message-ID: Date: 2 Jul 90 09:22:33 GMT References: <1990Jun29.123957.16727@eua.ericsson.se> Sender: chik@icot32.icot.or.jp Reply-To: chikayama@icot.or.jp Distribution: comp.lang.prolog Organization: Institute for New Generation Computer Technology, Tokyo, Japan. Lines: 33 In-reply-to: euakan@eua.ericsson.se's message of 29 Jun 90 12:39:57 GMT In article <1990Jun29.123957.16727@eua.ericsson.se> euakan@eua.ericsson.se (Theo.Kanter) writes: > THEORY? > Ulrich N. (below) reminded me of one aspect of the OO paradigm. > Namely, that objects have states. Now, neither mathematical logic or > lambda calculus on which we try to base pure logical and functional languages > provide for something called states. It seems to me that something is > missing here, and that concurrency as in GHC and the like has little to do > with it. Concurrency as in GHC has _much_ to do with object states actually. In object-oriented style GHC programs, processes correspond to objects, status of on-going computation corresponds to object states. This almost directly corresponds to Carl Hewitts' "actors". You might consider, however, that GHC or any other committed choice style languages are not logic programming languages, depending on what you mean by the words "logic programming". At 7th ICLP at Jerusalem: LINEAR OBJECTS: LOGICAL PROCESSES WITH BUILT-IN INHERITANCE Jean-Marc Andreoli, Remo Pareschi is presented, which explains "states" in the framework of "linear logic". The model is completely different from OOP in GHC, but linear logic also has much to do with concurrency. You (or Ulbricht Neumerkel) might, however, exclude this also, because the logic it is based on is not classical logic. Takashi Chikayama Institute for New Generation Computer Technology