Collected proofs can be used to give justifications about the behavior of a rule based expert system. In this paper, we chose the fault diagnosis problem as an application to demonstrate how multiple theories and fail branches in MetaProlog play a key role in the representation of this problem. For example, consider an object representing a switch. Meta-level programming and knowledge representation . A Web page becomes a live information entity that can determine its own response to queries.
Queries naturally map to goal evaluations.
This enables a page to reason about itself and other pages, access and manipulate pages, and define arbitrary relationships between pages. The Web page is fetched by Mosaic and installed by Prolog. Prolog executes the goal in the page. The syntax of live clauses has been kept as close as possible to that of ordinary Prolog. Meta-level Programming and Knowledge Representation .