R2ML is a markup language for rules developed in REWERSE I1 Working Group. It includes RIF BLD as a subset. As soon RIF-BLD the I1 working group will provide a transformation from RIF-BLD to R2ML.
R2ML is a usable language in the sense that it allows structure-preserving markup and does not force users to translate their rule expressions into a different language paradigm such as having to transform a derivation rule into a FOL axiom, an ECA rule into a production rule, a function into a predicate, or a typed atom into an untyped atom.
The main characteristic of this markup language is that it can be deployed to different Platform-Specific Rule Languages by means of translators. At this time we can translate R2ML rules to:
Almost of translators where built by using XSLT but some of them use ATL transformation language.
R2ML was also tested on UServ Use Case by translating and executing rules with Drools and translating and executing rules with Jena Rules. A rule browser is available for user which want to see the encoding of rules both in the markup and in the target language.
The Userv Use Case was also implemented with Take. A Java WebStart application is available.
A basic SOAP Web Service performing interchange is available.