Class Module Design Convention

Parametrized class instantiation
A pair of a factory and a custom constructor performs parametrized class instantiation. Default factory Create and default constructor Init are defined on the class's default interface only. Both methods have the same parameter signature but different return values. Factory should be a function returning a class instance, and constructor should be a sub with no return value. The factory method called on the default (predeclared) class's instance (enabled via the "Predeclared" attribute) generates a new object and then calls its constructor with all received arguments to complete initialization. To simulate rudimentary introspection, Class and Self getters can also be defined. The Class getter returns the class's default instance. If a class instance presents a non-default interface, Self should return it as well.

Abstract Factory
An abstract factory class has two default factory methods. The Create method follows the same convention as for a regular class. It is available on the default predeclared instance of the abstract factory only and generates factory instances. The other factory is CreateInstance. It must be available on non-default factory instances, but it can also be available on the default instance. This factory generates instances of the target class.

Multiple interfaces
Class interfaces enable better decoupling of components. Some classes implement multiple interfaces (analog of multiple inheritance). While their instances expose the implemented interfaces, a given reference exposes only one interface at a time. One possible approach to making all interfaces conveniently available is as follows. "Self<Interface name>" methods defined on the class's default interface return references to the instance's respective interfaces. Additionally, the CreateDefault constructor defined on the default interface generates class instances exposing the default interface.