Program development through proof transformation

Abstract

Abstract. We present a methodology for deriving veried programs that combines theorem proving and proof transformation steps. It extends the paradigm employed in systems like NuPrl where a program is developed and veried through the proof of the specication in a constructive type theory. We illustrate our methodology through an extended example | a derivation of Warshall's algorithm for graph reachability. We also outline how our framework supports the denition, implementation, and use of abstract data types.

The ergo support system: an integrated set of tools for prototyping integrated environments

“…We have experimented with many methods for formal program development, ranging from classical program transformation such as the fold/unfold system of Burstall and Darlington [BD77], finite differencing techniques of Paige and Koening [PK80], and the specialization system of Scherlis (see [Sch86] for references), to proof-based approaches such as the Nuprl system [CKB84,C*86] and proof transformation techniques [Pfe88b]. Our experiments with these and other approaches fall into three categories: (1) those done on paper only, (2) those using imported, existing systems, and (3) those carried out in environments which were constructed with the ESS.…”