Hoare-Style Proof Systems and Formal Computations

Hoare-style proof systems have been proposed for various language constructs [1]. Nevertheless, it is sometimes questioned as to what extent such systems can help to construct correct programs. One possible answer is provided by observing that efforts to find sound and complete Hoare-style proof systems can be considered as efforts to understand the formal computations of the considered programs. Stated in general terms this observation may seem quite obvious, but it is quite another matter to see what “understanding the formal computations” means for particular classes of programs.