On Behavioral Subtyping and Completeness
نویسندگان
چکیده
Behavioral subtyping forces objects of subtypes to behave in the same way as objects of supertypes. It is often favored over standard subtyping because it provides a means to obtain a modular program logic. Relative completeness is a formal property of a Hoare logic that ensures that any failed attempt to verify the correctness of a program is not caused by a weakness of its Hoare rules. In this paper, we argue that the standard relative completeness notion is too stringent for program logics that are based on behavioral subtyping. Subsequently, we propose two novel and complementary completeness notions that can be employed to assess the strength of program logics that rely on behavioral subtyping.
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