Hey James.

You should think less technical and more in that (I guess you will hate it) Business-IT-Alignment. Using Excel or DSL to specify business rules, so extract it from code and make it readable by non technical people. That’s the goal!

And Drools is a good tool for this job (and it is one of the goals, look at Guvnor and the BRMS), even if the problem doesn’t really need RETE algorithms and such.

Cheers

Bernd

Von: rules-users-bounces@lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] Im Auftrag von James Owen
Gesendet: Samstag, 10. Oktober 2009 09:03
An: Rules Users List
Betreff: Re: [rules-users] Better way to run each rule once?

[Warning:  This email may contain heretical thoughts.  Read at your own risk.] 

Again, not knowing all of the facts and project requirements, I can only say that, so far, it sounds like a great problem for Java or C or C++.   I prefer C++ to Java and C but that's a personal thing based on not needing to have "Java Expert" on my CV in order to get a job.  (I do know Java and started with it way back in 1997 with version 0.9x but I don't consider myself an expert yet.)  

The CLIPS rulebase is still the fastest bare-bones expert system except for OPSJ and TECH.  In addition, we have lots of experienced C++ programmers in the world and if we run low on C++ programmers then the Java programmers can be taught proper coding techniques and threading procedures not being used today.  [See?  I told you it was heresy.]  I wonder if Drools could be re-written in C++ ??  Sounds like a great project to me.  :-)

I say things like this, sometimes in jest and sometimes not, so that we, the techie programmers and developers, would stop and think about what we're doing and why.  Do we really need to have "Rulebase Programmer" on our CV so badly that we would use it where it is not needed?  I have seen rulebased systems used the wrong way on many projects and I just had to walk away.  But, enough philosophy for one evening.  Think about it and consider your own personal integrity - if you do you'll probably find yourself out of a job but you'll be happier while standing in the unemployment line and wondering "WHY??  Why didn't I just keep my big mouth SHUT??".  <grin>

SDG

James Owen

Founder October Rules Fest

Senior Consultant / Architect KBSC

http://www.kbsc.com

http://www.OctoberRulesFest.org

Twitter: OctRulesFest

Blogs:

http://JavaRules.blogspot.com [Rulebased Systems Blog]

http://ORF2009.blogspot.com [October Rules Fest Blog]

http://exscg.blogspot.com/ [Expert Systems Consulting Group Blog]

"If I have seen a little further it is by standing on the shoulders of giants."

Sir Isaac Newton in a letter to Robert Hooke, 5 Feb 1676

Come to October Rules Fest and stand on the shoulders of the Giants of the industry; if only for a week.

On Oct 9, 2009, at 8:13 PM, Dave Schweisguth wrote:

James,

On Fri, Oct 09, 2009 at 06:28:21PM -0500, James Owen wrote:

[...] The whole thing "sounds like" a procedural problem where values are

modified and rules are fired only once. [...]

You're right, and I've felt bad about using this very powerful system in
such a limited way. Nonetheless Drools feels like an excellent fit for us:
we do have the requirement of having rules editable by non-engineers, and
Drools provides all of the structure around that that we'd otherwise have
had to come up with, plus a lot of room to grow. I've actually been
wondering whether anyone would suggest a way to solve the problem by
designing the rules and/or facts differently!

I also left out various complications: we have other classes of facts on
the LHS, and Thing's attributes appear on the LHS as well as its
unmodifiable properties. I considered a design where attributes were first-
class facts, but it seemed to run in to the same problem. I don't think any
of that goes against your basic point, however. What I wonder is whether it's
an inappropriate problem for the tool or merely inexpert use of the tool.

Cheers,

--
| Dave Schweisguth                           http://schweisguth.org/~dave/ |
| Home: dave at schweisguth.org            Work: http://www.nileguide.com/ |
| For compliance with the NJ Right to Know Act: Contents partially unknown |
_______________________________________________
rules-users mailing list
rules-users@lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users