Path: utzoo!attcan!uunet!ncrlnk!ncrcae!ncr-sd!hp-sdd!hplabs!otter!dsr From: dsr@otter.hple.hp.com (Dave Raggett) Newsgroups: comp.sys.mac.hypercard Subject: Help wanted on HyperCard and Expert Systems Message-ID: <670002@otter.hple.hp.com> Date: 22 Sep 88 17:03:43 GMT Organization: Hewlett-Packard Laboratories, Bristol, UK. Lines: 26 I am a newcomer to the Mac and would like to use HyperCard as the user interface for expert systems which will be implemented in Prolog. Is it possible to co-routine HyperCard and Prolog, so that you can prove Prolog goals from HyperTalk scripts and also get Prolog to send HyperTalk messages back to HyperCard? LPA (who supply MacProlog) say that they have had a lot of requests, but that you can't call MacProlog as yet. They intend to release a version with this feature in about one years time. What about other Prologs? So far I have two ideas: 1) To implement a simple prolog interpreter in C as a XCMD with entry points for initializing stacks, proving goals and freeing resources. Can you send messages to HyperCard from XCMDs? 2) To run Prolog (e.g. MacProlog) in the background (under MultiFinder), and get it to call a C predicate which blocks waiting for a service request. You then need to find a way to get HyperCard to send such a request and wait for a reply. This is all very hazy to me! I'm sorry if my lack of knowledge shows, but I would be very grateful for any ideas. Dave (hopeful) Raggett - in darkest Bristol, England.