I'm trying to use LISA for our company inhouse use.
LISA is a lisp rules engine.
I'm new to this rules engine thing.
I read a little bit some articles about rule engines and found out that
there are 2 different types of rule engines - forward and backward
chaining.
As I understand with backward chaining I can ask questions to rule
engine like "Is this order ready for billing ?"
With forward chaining i can authomate some work, like "As soon as
payment is received - ship ordered parts"
Maybe i'm wrong, maybe i understood all this incorrectly.
Anyway I downloaded LISA and developed with it a simple rule engine
application that answers to questions like "Is this order ready for
billing".
So i quess LISA is backward chaining rule engine. Or maybe i'm wrong.
Can anyone comment on that ?
What kind of rule engine is LISA ?
Vagif Verdi wrote:
> What kind of rule engine is LISA ?
LISA is a forward chaining rule engine. Backward chaining ison
the list of things to do. (This is mentioned in the reference
manual).
"Vagif Verdi" <···········@gmail.com> writes:
> I'm new to this rules engine thing.
I recommend the books I mentioned in this blog entry:
LISA and rule-based programming in Common Lisp
http://www.paoloamoroso.it/log/050827.html
> So i quess LISA is backward chaining rule engine. Or maybe i'm wrong.
Lisa is a forward-chaining system. The book by Giarratano (see
above), if I recall correctly, explains how to implement a
backward-chaining system with a forward-chaining one.
Paolo
--
Why Lisp? http://wiki.alu.org/RtL%20Highlight%20Film
The Common Lisp Directory: http://www.cl-user.net
Thanks for clarification.
I'm currently evaluating KnowledgeWorks that is included into
Enterprise version of LispWorks.
It's synthax is very similar to synthax of LISA. So rules I wrote in
LISA would be very easy to transfer to KnowledgeWorks.
KnowledgeWorks also has backward chaining, using full implementation of
Prolog.
One of these 2 rule engines i think will be used by me in production.
Can anyone comment on comparison of these 2 rule engines ? Or maybe on
his experience with KnowledgeWorks ? Any downsides i should know about
?
Also i've seen that ACL lisp has integrated simple version of Prolog,
that they are using as query engine for AllegroCache.
Do they also have any kind of rule engine coming with ACL ?
KnowledgeWorks is first-class. If you're looking at a serious
commercial application, or need the power of queries and
backward-chaining, KW is the way to go.
-- david
I'm sorry David.
I did not realize first that you are an author of LISA.
Actually i liked LISA alot. In fact so much that I hesitated to try
KnowledgeWorks.
Your recomendation means alot to me.
I'll certanly give a cerious try to KnowledgeWorks.
Hi. Thanks very much for the compliment. Yes, I have a fair amount of
experience with KW in a commercial setting. It all depends on what you
need and what you're willing to live with. From everything I can
determine, Lisa is very stable and usable. As I've mentioned, I feel
Lisa's biggest disadvantage right now is its lack of a
backward-chaining interpreter (and a corresponding robust query
interface); other than that Lisa is feature complete for the most part.
Support is another issue you'll need to consider. I have zero time to
work on Lisa right now and I don't see that changing in the near
future; KW, of course, is backed by Lispworks and their support team is
excellent.
If you're doing research, or want to build a small internal system with
no start-up costs, Lisa should be perfect. If you're building a
commercial system and must have support, look seriously at KW. If
you're building a commercial system and can handle extending Lisa to
meet your needs, consider both.
Cheers, David.
For wisdom is more precious than rubies,
and nothing you desire can compare with her.
-- Proverbs 8:11
But all the world understands my language.
-- Franz Joseph Haydn
We are definitely going to purchase and use Lispworks and
KnowledgeWorks.
Regarding your last suggestion "consider both".
Is there any reason I would use both LISA and KnowledgeWorks together ?