Semantic subtyping between coinductive mutable record types with unions and intersections
نویسندگان
چکیده
Semantic subtyping between coinductive record types supports accurate type analysis of object-oriented languages, by introducing Boolean type constructors and modeling cyclic objects. In previous work, a sound and complete algorithm for semantic subtyping has been proposed, but only for coinductive immutable record types with unions. In this work we address the issue of extending the previous results to the more challenging case where records can be mutable, and, besides union, also intersection types are supported. We provide a set of subtyping rules on top of which a sound decision algorithm can be defined.
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