System F with Width-Subtyping and Record Updating
نویسنده
چکیده
It is a well-known problem that F { the polymorphic lambda calculus F extended with subtyping { does not provide so-called polymor-phic updates, and that the standard PER model for F does not provide interpretations for these operations. The polymorphic updates are interesting because they play an important role in some type-theoretic models of object-oriented languages. We present an extension F width of system F with a restricted form of subtyping { width-subtyping { on record types, that does provide these operations. The main result is that we show it is still possible to give a PER model for this system.
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