Arithmetic Equality Constraints as C++ Statements

A computer program in a conventional (imperative) language provides an explicit sequence of instructions by which to compute the desired answer. A program in a declarative language, by contrast, expresses conditions that the answer should satisfy; it is up to an implementation of the language to compute an appropriate answer. The usefulness of declarative programming has been recognized for decades, especially for graphics; Leler l summarizes earlier work, including that of Sutherland, 2 Borning, 3 and Van Wyk. 4 This article describes how one can add some declarative features to the (imperative) C++ language, using only features of and functions written in the language itself