Applying 'design by contract'

Methodological guidelines for object-oriented software construction that improve the reliability of the resulting software systems are presented. It is shown that the object-oriented techniques rely on the theory of design by contract, which underlies the design of the Eiffel analysis, design, and programming language and of the supporting libraries, from which a number of examples are drawn. The theory of contract design and the role of assertions in that theory are discussed.<>