Let Generalization, Polymorphic Recursion, and Variable Minimization in Boolean-Kinded Type Systems
Abstract
Recent research has demonstrated the effectiveness of extending the Hindley-Milner (HM) type system with Boolean kinds to support type inference for a wide variety of features. However, the means to support classic type system provisions such as local let generalization and polymorphic recursion is either limited or unknown for such extensions. This paper contributes procedures for equational generalization and semiunification in arbitrary Boolean rings, enabling let generalization and polymorphic recursion in Boolean-kinded type inference. Additionally, methods to minimize the number of bound Boolean type variables are developed to keep types small in these systems. Boolean-kinded HM extensions are exemplified with nullable reference types , and how to use the developed procedures to support let generalization and polymorphic recursion is outlined.
Fields of Study & Subjects
Logic
programming
and type systems
Formal Methods in Verification
Constraint Satisfaction and Optimization
Publication details
- Journal / source
- Proceedings of the ACM on Programming Languages
- Publisher
- Association for Computing Machinery (ACM)
- Volume
- 10
- Issue
- POPL
- Pages
- 33–63
- Publication date
- 8 January 2026
- Language
- EN