Subtyping Constrained Types
نویسندگان
چکیده
A constrained type is a type that comes with a set of subtyping constraints on variables occurring in the type. Constrained type inference systems are a natural generalization of Hindley/Milner type inference to languages with subtyping. This paper develops several subtyping relations on polymorphic constrained types of a general form that allows recursive constraints and multiple bounds on type variables. Subtyping constrained types has applications to signature matching and to constrained type simplification.
منابع مشابه
Subtyping Constrained Types ( Draft ) Valery Trifonov
Constrained type systems are a natural generalization of Hindley/Milner type inference to languages with subtyping. This paper develops several subtyping relations on constrained types. We establish a full type abstraction property that equates an operational notion of subtyping with a semantic notion based on regular trees. The decidability of this notion of subtyping is open; we present a dec...
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