Hostname: page-component-8448b6f56d-wq2xx Total loading time: 0 Render date: 2024-04-18T03:31:41.669Z Has data issue: false hasContentIssue false

Provable isomorphisms of types

Published online by Cambridge University Press:  04 March 2009

Kim B. Bruce
Affiliation:
Dept. of Computer Science, Williams College, Williamstown, MA 01267
Roberto Di Cosmo
Affiliation:
Dip. di Informatica, Università di Pisa, Italy, and LIENS, 45, Rue d'Ulm, Paris, France
Giuseppe Longo
Affiliation:
LIENS (CNRS) – DMI, Ecole Normale Superieure, 45, Rue d'Ulm, Paris, France

Abstract

A constructive characterization is given of the isomorphisms which must hold in all models of the typed lambda calculus with surjective pairing. Using the close relation between closed Cartesian categories and models of these calculi, we also produce a characterization of those isomorphisms which hold in all CCC's. Using the correspondence between these calculi and proofs in intuitionistic positive propositional logic, we thus provide a characterization of equivalent formulae of this logic, where the definition of equivalence of terms depends on having “invertible” proofs between the two terms. Work of Rittri (1989), on types as search keys in program libraries, provides an interesting example of use of these characterizations.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Alessi, F. and Barbanera, F. (1991) Strong conjunction and intersection types. Dipartimento di Informatica, Università di Torino (Italy), manuscript.CrossRefGoogle Scholar
Asperti, A. and Longo, G. (1991) Categories, Types, and Structures. MIT Press.Google Scholar
Barendregt, H. (1984) The Lambda Calculus; Its syntax and Semantics (revised edition). North Holland.Google Scholar
Bruce, K. and Longo, G. (1985) Provable isomorphisms and domain equations in models of typed languages. ACM Symposium on Theory of Computing (STOC 85).CrossRefGoogle Scholar
Babaev, A. A. and Soloviev, S. V. (1982) Coherence theorem for canonical maps in certesian closed categories. Journal of Soviet Mathematics, 20.Google Scholar
Curien, P.-L. and Cosmo, Di. (1991) A confluent reduction system for the λ-calculus with surjective pairing and terminal object. In Leach, Monien, , and Artalejo, , editors, ICALP, pages 291302. Springer-Verlag.Google Scholar
Di Cosmo, R. and Longo, G. (1989) Constuctively equivalent propositions and isomorphisms of objects (or terms as natural transformations). Workshop on Logic for Computer Science – MSRI, Berkeley.Google Scholar
Dezani-Ciancaglini, M. (1976) Characterization of normal forms possessing an inverse in the λβη calculus. Theoretical Computer Science, 2:323–337.CrossRefGoogle Scholar
Lopez-Escober, E. G. K. (1985) Proof functional connectives. Lecture Notes in Mathematics, 1130:208221.CrossRefGoogle Scholar
Lambek, J. and Scott, P. J. (1986) An introduction to higher order categorical logic. Cambridge University Press.Google Scholar
Martin, C.F. (1972) Axiomatic bases for equational theories of natural numbers. Notices of the Am. Math. Soc., 19(7):778.Google Scholar
Martini, S. (1991) Strong equivalence in positive propositional logic: provable realizability and type assignment. Dipartimento di Informatics, Università di Pisa (Italy,) Internal Note., 06 1991.Google Scholar
Narendran, P., Pfenning, F.and Statman, R. (1989) On the unification problem for cartesian closed categories. Hardware Verification Workshop, 09 1989.Google Scholar
Pottinger, G. (1981) The Church Rosser Theorem for the Typed lambda-calculus with Surjective Pairing. Notre Dame Journal of Formal Logic, 22(3):264268.CrossRefGoogle Scholar
Reynolds, J.C. (1984) Polymorphism is not set-theoretic. Lecture Notes in Computer Science, 173.CrossRefGoogle Scholar
Rittri, M. (1989) Using types as search keys in function libraries. Journal of Functional Programming, 1(1).Google Scholar
Rittri, M. (1990) Retrieving library identifiers by equational matching of types. 10th Int. Conf. on Automated Deduction. Lecture Notes in Computer Science, 449, 07 1990.CrossRefGoogle Scholar
Soloviev, S. V. (1983) The category of finite sets and cartesian closed categories. Journal of Soviet Mathematics, 22(3):13871400.CrossRefGoogle Scholar
Statman, R. (1983) λ-definable functionals and βη conversion. Arch. Math. Logik, 23:2126.CrossRefGoogle Scholar