W3C Rules Interchange Format(Basic Logic Dialect)
Chris Welty IBM Research & RIF WG co-Chair
September 17th, 2009 - New York, NY
Rule Interchange Format (RIF) is a proposed recommendation of the World Wide Web Consortium to provide a format for the interchange of rules in rule-based systems on the semantic web. The goal is to create an interchange format for different rule languages and inference engines.
RIF describes a number of dialects, initially including a Basic Logic Dialect (BLD) and Production Rule Dialect (PRD). RIF can be viewed as a specification language for data. The presentation language uses the Prolog operator ':-', which places the conclusion of the rule first and the premises afterwards. As a result, RIF rules presented in this language are best read from the bottom up. RIF also incorporates a slot notation indicated with brackets to express assertions about the bindings that associate variables (on the left side of a binding) with values (on the right side of the binding).
The semantics of RIF are defined by interpreting each expression in the presentation language as a corresponding RDF expression. The semantics of an expression can be understood either by reading the presentation language expression or by reading the corresponding RDF. Usually, people will prefer to read the presentation language version.