Computer Science – Programming Languages
Scientific paper
2010-06-08
EPTCS 25, 2010, pp. 214-230
Computer Science
Programming Languages
Scientific paper
10.4204/EPTCS.25.20
In recent work we have shown how it is possible to define very precise type systems for object-oriented languages by abstractly compiling a program into a Horn formula f. Then type inference amounts to resolving a certain goal w.r.t. the coinductive (that is, the greatest) Herbrand model of f. Type systems defined in this way are idealized, since in the most interesting instantiations both the terms of the coinductive Herbrand universe and goal derivations cannot be finitely represented. However, sound and quite expressive approximations can be implemented by considering only regular terms and derivations. In doing so, it is essential to introduce a proper subtyping relation formalizing the notion of approximation between types. In this paper we study a subtyping relation on coinductive terms built on union and object type constructors. We define an interpretation of types as set of values induced by a quite intuitive relation of membership of values to types, and prove that the definition of subtyping is sound w.r.t. subset inclusion between type interpretations. The proof of soundness has allowed us to simplify the notion of contractive derivation and to discover that the previously given definition of subtyping did not cover all possible representations of the empty type.
Ancona Davide
Lagorio Giovanni
No associations
LandOfFree
Coinductive subtyping for abstract compilation of object-oriented languages into Horn formulas does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Coinductive subtyping for abstract compilation of object-oriented languages into Horn formulas, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Coinductive subtyping for abstract compilation of object-oriented languages into Horn formulas will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-29343