Polarized Higher-Order Subtyping

Polarized Higher-Order Subtyping (1997)

by Martin Steffen

Citations:

28 - 1 self

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Datum	Value	Source
TITLE	Polarized Higher-Order Subtyping	user correction
AUTHOR NAME	Martin Steffen	user correction
AUTHOR AFFIL	Universität Erlangen-nürnberg	user correction
ABSTRACT	The calculus of higher order subtyping, known as F ω ≤ , a higher-order polymorphic λ-calculus with subtyping, is expressive enough to serve as core calculus for typed object-oriented languages. The versions considered in the literature usually support only pointwise subtyping of type operators, where two types S U and T U are in subtype relation, if S and T are. In the widely cited, unpublished note [Car90], Cardelli presents F ω ≤ in a more general form going beyond pointwise subtyping of type applications in distinguishing between monotone and antimonotone operators. Thus, for instance, T U1 is a subtype of T U2, if U1 ≤ U2 and T is a monotone operator. My thesis extends F ω ≤ by polarized application, it explores its proof theory, establishing decidability of polarized F ω ≤. The inclusion of polarized application rules leads to an interdependence of the subtyping and the kinding system. This contrasts with pure F ω ≤ , where subtyping depends on kinding but not vice versa. To retain decidability of the system, the equal-bounds subtyping rule for all-types is rephrased in the polarized setting as a mutual-subtype requirement of the upper bounds.	SVM HeaderParse 0.2
YEAR	1997	user correction
CITATIONS	6 found	ParsCit 1.0