Details

Autor(en) / Beteiligte

• Fisher, Kathleen
• Mitchell, John C.

Titel

A delegation-based object calculus with subtyping

Ist Teil von

• Fundamentals of Computation Theory, 2005, p.42-61

Ort / Verlag

Berlin, Heidelberg: Springer Berlin Heidelberg

Erscheinungsjahr

2005

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• This paper presents an untyped object calculus that reflects the capabilities of so-called delegation-based object-oriented languages. A type inference system allows static detection of errors, such as message not understood, while at the same time allowing the type of an inherited method to be specialized to the type of the inheriting object. The main advance over previous work is the provision for subtyping in the presence of delegation primatives. This is achieved by distinguishing a prototype, whose methods may be extended or replaced, from an object, which only responds to messages for which it already has methods. An advantage of this approach is that we have full subtyping without restricting the “runtime” use of inheritance. Type soundness is proved using operational semantics and an analysis of typing derivations.