SWSL-Rules is a rule-based language, which can be used both as a specification and an implementation language for Semantic Web Services. SWSL-Rules is based on F-logic, HiLog, and Courteous Logic Programming.
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This language incorporates many of the features that are deemed necessary for a RIF language. These include full Horn support, frames, higher-orderness, defaults.
Impact on Design
SWSL-Rules provides an example of a language design that incorporates many features that are important to RIF.
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