Covariant types
نویسندگان
چکیده
منابع مشابه
A Fresh Look at Parametric Polymorphism: Covariant Types
The covariant type system is rich enough to represent polymorphism on inductive types, such as lists and trees, and yet is simple enough to have a set-theoretic semantics. Its chief novelty is to replace function types by transformation types, which denote parametric functions. Their free type variables are all in positive positions, and so can be modelled by covariant functors. Similarly, term...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 1997
ISSN: 0304-3975
DOI: 10.1016/s0304-3975(97)00045-5