Semantics and correctness of nondeterministic flowchart programs with recursive procedures

Completeness with Finite Systems of Intermediate Assertions for Recursive Program Schemes

“…Since proofs are finite, we obtain a finite system of intermediate assertions, thus apparently contradicting the result of [2]. Also [ 4] and [6] avoid the necessity of an infinite number of assertions by using an extension of the inductive assertion method.…”

“…The purpose of this paper is to investigate this issue in the 'relational framework of [2] and to obtain, within that framework, a unification of the (essence of the) results of [2] and of [ 4], [5] and [6]. The solution of the apparent contradiction lies in the fact that in [4], [5] and [6] auxiliary variables are used (to store the initial values of variables).…”

“…The solution of the apparent contradiction lies in the fact that in [4], [5] and [6] auxiliary variables are used (to store the initial values of variables). These auxiliary variables have no semantic counterpart in the relational framework of [2].…”

Formal computations of non deterministic recursive program schemes

“…Under natural hypothesis the set of finite and infinite trees generated by a scheme is proved to be the greatest fixed point of the functional mapping usually attached to this scheme.[ntroduction Several authors have been recently interested in non deterministic recursive programs [1,5,11,13,14,15,16,17].These programs are obtained by introducing a connective or which has to be interpreted operationally as giving alternatives of a choice. Under natural hypothesis the set of finite and infinite trees generated by a scheme is proved to be the greatest fixed point of the functional mapping usually attached to this scheme.…”

“…[ntroduction Several authors have been recently interested in non deterministic recursive programs [1,5,11,13,14,15,16,17].…”