Combining subsumption and binary methods: an object calculus with views

We presen t an object-oriented calculus whic hallows arbitrary hiding of methods in protot ypes, even in the presence of binary methods and friend functions. This combination of features permits complete control of the in terface a class exposes to the remainder of a program (which is of key importance for program readability, security and ease of maintenance), while still allowing complex in teractions with other classes belonging to the same module or softw are component.This result is made possible by the use of views. A view is a name that specifies an in terface to an object. A set of views is attached to each object and a method can be invoked either directly or via a view of the object.