Subtypes for specifications: predicate subtyping in PVS
John Rushby, Sam Owre, Natarajan Shankar · IEEE Transactions on Software Engineering · 1998
A specification language used in the context of an effective theorem prover can provide novel features that enhance precision and expressiveness. In particular, type checking for the language can exploit the services of the theorem prover. We describe a feature called "predicate subtyping" that uses this capability and illustrate its utility as mechanized in PVS.