Encoding a dependent-type -calculus in a logic programming language
Résumé
Various forms of typed l-calculi have been proposed as specification languages for representing wide varieties of object logics. The logical framework, LF is an example of such a dependent-type l-calculus. A small subset of intuitionistic logic with quantification over simply typed l-calculus has also been proposed as a framework for specifying general logics. The logic of hereditary Harrop formulas with quantification at all non-predicate types, denoted here as hhw is such a meta-logic that has been implemented in both the Isabelle theorem prover and the lProlog logic programming language. In this paper, we show how LF can be encoded into hhw in a direct and natural way by mapping the typing judgments in LF into propositions in the logic of hhw. This translation establishes a strong connection between these two languages : the order of quantification in an LF signature is exactly the order of a set of hhw clauses and the proofs in one system correspond directly to proofs in the other system.