An algebraic model of sybtypes in object-oriented languages (draft)

An algebraic notion of type and subtype is developed appropriate to modelling strict object-oriented inheritance. “Subtype” is a binary relation between algebras defined in terms of property-preserving mappings (coercions) that have nice composition properties with regard to function types, record types, and inheritance. Algebraic models are related to models of subtype polymorphism in the second order (polymorphic) lambd a calculus. The notation of bounded quantification is introduced and its use in modelling inheritance is examined. Table of