Patterns for Coping with Copying in C++ Clone Alone

A pattern identifies a general approach to solving a problem, typically capturing a solution practice or collaborative structure. It identifies the general context of the problem, the nature of the problem, the interplay of conflicting forces, the configuration that resolves the problem, and the resulting context of applying such a solution. In short: where, what and how the problem arises and is solved. Rather than living in the abstract, a pattern needs to be illustrated by something concrete, such as a specific example with code and diagrams. There are many forms for documenting patterns [Coplien1996], ranging from the highly structured heading-based template form used by the Gang of Four [Gamma+1995], to the more narrative form used by Alexander [Alexander+1977, Alexander1979]. In each form we should be able to find the essential elements I have just described. For this article I intend to use a relatively low-ceremony form structured around problem, solution and discussion sections. Patterns can be grouped together and collected in a catalogue to provide a useful knowledge source, a simple software engineering handbook if you like. However, the full power of patterns is realised by connecting them together in a narrative structure called