Rather than re-inventing the wheel, I’d suggest you to use some readily available solution. There are several expert systems out there and I’ll focus on those which are either in Python or can be used via Python. CLIPS CLIPS is an expert system originally developed by NASA. It’s considered state of the art and used … Read more
There’s also nools, give it a try.
Fanatics of all stripes should be questioned, no matter what topic they rave about. Data-driven decision tables are a perfectly good way to implement complex behavior. On the day it doesn’t scale or perform to your requirements, perhaps you’ll want to consider something else. I wouldn’t want to make a technology swap in working production … Read more
You should check out the Rules Design Pattern http://www.michael-whelan.net/rules-design-pattern/. It looks very similar to the example code you gave and consists of a base interface that defines a method for determining if a rule is satisfied and then various concrete implementations per different rules. As I understand it, your switch statement would turn into some … Read more
Implementing a simple rule-based evaluation system in Java isn’t that hard to achieve. Probably the parser for the expression is the most complicated stuff. The example code below uses a couple of patterns to achieve your desired functionality. A singleton pattern is used to store each available operation in a member map. The operation itself … Read more
I’ve implemented a (more complicated) version of what you are describing in c#, and thinking back through the code, all of it would be doable with JavaScript. I agree with the comments posted that writing your own is a viable option. It can be as simple or complex as you want it to be. General … Read more
Agreeing with will I would say use something from the workflow engine family although not workflow. Examine System.Workflow.Activities.Rules Namespace a little bit – it’s supported in .Net 3, and built into .Net3.5. You have everything in hand for free to use like you mentioned : RuleCondition for conditions , RuleAction for actions standardized format for … Read more
Most rule engines that I have seen are viewed as a black box by system code. If I were to build a domain model, I would probably want certain business rules to be intrinsic to the domain model, e.g. business rules that tell me when an object has invalid values. This allows multiple systems to … Read more
I will give 2 examples from personal experience where using a Rules Engine was a bad idea, maybe that will help:- On a past project, I noticed that the rules files (the project used Drools) contained a lot of java code, including loops, functions etc. They were essentially java files masquerading as rules file. When … Read more
What are the pros and cons to adopting the Java rules engines JESS and Drools? Use a rule engine if you need to separate the business rules from the application logic. The Does Your Project Need a Rule Engine article has a good example: For example, a typical storefront system might involve code to calculate … Read more