Basic theory of F-bounded quantification

Paolo BALDAN, Giorgio GHELLI, Alessandra RAFFAETÀ Dipartimento di Informatica, Corso Italia, 40, 56125 Pisa, Italy E-mail:{baldan, ghelli, raffaeta}@di.unipi.it  

Abstract:

System F-bounded is a second order typed lambda calculus, where the basic features of object-oriented languages can be naturally modelled. F-bounded extends the better known system , in a way that provides an immediate solution for the treatment of the so-called ``binary methods''. Although more powerful than and also quite natural, system F-bounded has only been superficially studied from a foundational perspective and many of its essential properties have been conjectured but never proved in the literature. The aim of this paper is to give a solid foundation to F-bounded, by addressing and proving the key properties of the system. In particular transitivity elimination, completeness of the type checking semi-algorithm, the subject reduction property for reduction, conservativity with respect to system and antisymmetry of a ``full'' subsystem are considered, and various possible formulations for system F-bounded are compared. Finally a semantic interpretation of system F-bounded is presented, based on partial equivalence relations.