Templatized Primitive Method Idiom

Template Method Pattern (see [5]) solves the problem of the existence of a generic algorithm for a family of classes that needs specialization in each and every concrete class. It does so by implementing the algorithm in the base class and by forwarding implementation details to (pure) virtual functions. In terms of [5] these forwarding functions are called primitive. In this paper we propose an implementation of the Template Method Pattern in C++ that addresses the question of stronger insulation of primitive functions, in the sense of [7], and of better conformance to the Open Closed Principle of Bertrand Meyers (see [9]). Mixing virtual functions and templates the Templatized Primitive Method Idiom gives an example of mixing subtype and parametric polymorphism in what we believe is an interesting and powerful idiom.