Thanks for posting. I will certainly explore this. Did you look at Mimir? https://github.com/hraberg/mimir Could you outline how is Clara's approach different from Mimir?
Shantanu On Sunday, 18 August 2013 23:46:14 UTC+5:30, Ryan Brush wrote: > > Perhaps the best aspect of Clojure is how it can adopt the best ideas from > other domains to concisely solve problems, as we've seen with core.logic, > core.async and other libraries. I recently came across a problem domain > that is easily expressed in forward-chaining rules, and found Clojure to be > a powerful way to solve it. > > While working through this problem space I started to suspect there is a > more general need for forward-chaining rules in Clojure to complement > core.logic and other libraries. So as a side project I implemented a raw > but working engine to do so. I'm posting here to share a draft of this > engine, its major design goals, and to ask for input on how we should > approach forward-chaining rules in Clojure in general. > > The rationale and some examples are on the github page for this > engine<https://github.com/rbrush/clara-rules>, > which I've tentatively named Clara. The state of the code isn't where it > needs to be yet; I've been learning the intricacies of Rete and discovering > better ways to solve problems along the way, and some of that is reflected > in the code base. However, the major pieces of design and functionality are > in place, so I'd like to get input on those. > > The idea is to draw a bit from Jess and Lisa, with the Java interop > strength of Drools, but the advantages and idioms available in Clojure. The > major goals are: > > - Focus on problem spaces naturally expressed as forward-chaining > rules. Data-driven needs like eventing, data validation, or application of > arbitrary business rules fit here. > - Embrace immutability. The rule engine's working memory is a > persistent Clojure data structure that can participate in transactions. > All > changes produce a new working memory that shares state with the previous. > - Rule constraints and actions are simply Clojure s-expressions. > - First-class Java interoperability and APIs. This should be an > alternative to Jess or Drools from Java-land. > - Usable either as a library to simplify Clojure code, or as a DSL to > externalize business logic. > - Working memory facts are typically (but not exclusively) Clojure > records or Java objects following the Java Bean conventions. > - Support the major advantages of existing rules systems, such as > explainability of why a rule fired and automatic truth maintenance. > - Collections of facts can be reasoned with using accumulators similar > to Jess or Drools. These accumulators leverage the reducers API and are > transparently parallelized. > - The working memory is independent of the logic flow, and can be > replaced with a distributed processing system. A prototype that uses > Storm <https://github.com/rbrush/clara-storm> to apply rules to a > stream of incoming events already exists. > > I'd love to hear thoughts on a couple questions: > > What else would you want from a forward-chaining rules engine in Clojure? > What design changes would you make, given the above criteria and examples > on github? > > All thoughts are appreciated! > > -Ryan > > https://github.com/rbrush/clara-rules > https://github.com/rbrush/clara-examples > https://github.com/rbrush/clara-storm > > -- -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
