Sigma predicates of finite types

Separation Logic Predicates for Aggregate Data Types

Many imperative languages have type systems built from a few elementary types with rules for building aggregate types. In C, integers, floating point numbers, and pointers are elementary types; struct, union and array build aggregates. When using separation logic to write assertions for such languages, one uses separating conjunction ∗ to describe aggregate values in memory. These conjunctions ...

Constructive Membership Predicates as Index Types

In the constructive setting, membership predicates over recursive types are inhabited by terms indexing the elements that satisfy the criteria for membership. In this paper, we motivate and explore this idea in the concrete setting of lists and trees. We show that the inhabitants of membership predicates are precisely the inhabitants of a generic shape type. We show that membership of x (of typ...

Finite Automata with Predicates for NLP

Finite State Transducers with Predicates and Identities

An extension to finite state transducers is presented, in which atomic symbols are replaced by arbitrary predicates over symbols. The extension is motivated by applications in natural language processing (but may be more widely applicable) as well as by the observation that transducers with predicates generally have fewer states and fewer transitions. Although the extension is fairly trivial fo...

Combining Incoherent Coercions for Sigma-Types