A computer-implemented method of processing a module specification to produce a module definition is disclosed. A module consists of a collection of interrelated classes for object-oriented programming. A module specification is an object-oriented data structure, the elements of which correspond to classes of a meta-module. A module definition is a collection of class definitions and other expressions in an object-oriented programming language. The module specification includes unitary and categorical class specifications. The class specifications include member specifications. The module definition may include definitions for a unitary host class, a unitary viewer class, a unitary editor class, and categorical class definitions corresponding to the categorical class specifications.