Information and Computation - Semantics of Data Types
TAPSOFT '89 2nd international joint conference on Theory and practice of software development
Handbook of logic in computer science (vol. 2)
Information and Computation
Checking algorithms for pure type systems
TYPES '93 Proceedings of the international workshop on Types for proofs and programs
Hi-index | 0.00 |
Pure Type Systems with universes (γPTS) provide a right frame to model programming languages features and are the core of Logical Frameworks, widely used in theorem proof systems. For these systems some authors propose a single rule, which includes both typing under β-conversion and the relation between universes. Our proposal adds an independent rule parameterized over a relation γ between sorts. Non trivial properties of the PTS like the weak strengthening lemma can be obtained in γPTS by extending a method proposed by van Benthem Jutting and using weak-closure for γreduction. This lemma is important due to two main reasons: (1) it provides a condensing lemma that determines in the underlying logic system a cut rule that simplifies the task in proof assistant systems; (2) the proof of type checking decidability can be eased in some normalizing systems.