Computer Science Department
School of Computer Science, Carnegie Mellon University
Admissibility of Fixpoint Induction over Partial Types
In this paper I present two new tools, predicate-admissibility and monotonicity, for showing types to be admissible. These tools show a wide class of types to be admissible; in particular, they show many dependent products to be admissible. This alleviates difficulties in applying partial types to theorem proving in practice. I also present a general least upper bound theorem for fixed points with regard to a computational approximation relation, and show an elegant application of the theorem to compactness.