Hi Tim,

   That is a nice topic for studies, but be prepared for a tsunami of information and quite a few controversies. :)

   Regarding your question, I am not sure I completely understand what you mean, but it is important to be clear that "generation of code" is an orthogonal concern to the chosen algorithm. I.e., take the Rete algorithm for example: you can have it fully "interpreted" (I am using the term loosely here), you can generate code for it completely, or you can be anywhere in the middle. In all cases, the properties of the algorithm itself will be preserved (assuming the implementations are correct). Incurring the risk of making a mistake here, I will mention that AFAIK Jess falls in the first cathegory, OPSJ falls in the second and Drools falls in the 3rd, and they are all Rete based algorithms.

   Its been a long time since I last looked at TAKE, but at that time it was generating code for a backward-chaining-like algorithm. Not sure what it has now.

   So, my suggestion is that you either focus on the properties of the algorithms itself (for instance, are you comparing classic Rete with known algorithm like LEAPS, TREAT, etc) or focus on the advantages and disadvantages of code generation (for instance "interpreted Rete" versus "code generated Rete", again using terms loosely here). Mixing everything in a single comparison might be misleading.

   Edson

2010/3/8 Tim de Jager <tim.dejager@student.hu.nl>

Hi everybody,

I'm currently doing my bachelor thesis on Rule engines. This includes
comapring different Rule engine products. I have set up a small Java program
(Conway's game of life) and I'm writing the 'engine' in different Rule
engines, while keeping the same GUI,CellGrid etc. I have already made a
Drools based engine.

I have been studying the Rule engine subject for somewhat more then a month
now. And I'm currently seeing two different developments namely the use of
an inference engine and the generation of embedded code instead (Take,
Visual Rules etc.)  I can see some of the pro's and cons with both
paradigms. But I'm wondering what opinion some of you guys have on the
subject.

I can see that without inferencing  it is very hard (or even impossible) to
keep a statefull session inside the rule engine, haven't seen a
non-inferencing rule engine which does offer this possibility. And also lose
features like TMS. But what would be a concrete example where a statefull
session is absolutely necessary? Instead of letting the engine reason over
all the facts in stateless way. And managing conflicts with a ruleflow (see
Visual Rules for a nice example).

I'm looking forward to hearing your thoughts.

Thanks,

Tim

P.S I already read two of Mark Proctors blogs on inferencing, but while
enlightening, they didn't supply me with a definitive awnser
--
View this message in context: http://n3.nabble.com/Inferencing-tp435411p435411.html
Sent from the Drools - User mailing list archive at Nabble.com.
_______________________________________________
rules-users mailing list
rules-users@lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users



--
 Edson Tirelli
 JBoss Drools Core Development
 JBoss by Red Hat @ www.jboss.com