Accession Number:

ADA210833

Title:

Type Reconstruction with First-Class Polymorphic Values

Descriptive Note:

Technical rept.

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE LAB FOR COMPUTER SCIENCE

Personal Author(s):

• O'Toole, James W.
• Gifford, David K.

Report Date:

1989-05-01

Pagination or Media Count:

14.0

Abstract:

We present the first type reconstruction system which combines the implicit typing of ML with the full power of the explicity typed second-order polymorphic lambda calculus. The system will accept ML-style programs, explicity typed programs, and programs that use explicit types for all first-class polymorphic values. We accomplish this flexibility by providing both generic and explicitly-quantified polymorphic types, as well as operators which convert between these two forms of polymorphism. This type reconstruction system is an integral part of the FX-89 programming language. We present a type reconstruction algorithm for the system. The type reconstruction algorithm is proven sound and complete with respect to the formal typing rules.

Descriptors:

• *COMPUTER PROGRAMMING
• *POLYMORPHISM
• VALUE
• POWER

Subject Categories:

• Computer Programming and Software

Distribution Statement:

APPROVED FOR PUBLIC RELEASE