Declarative Diagnosis of Missing Answers in Constraint Functional-Logic Programming

Abstract. We present a declarative method for diagnosing missing computed answers in CFLP(D), a generic scheme for lazy Constraint Functional-Logic Programming which can be instantiated by any constraint domain D given as parameter. As far as we know, declarative diagnosis of missing answers in such an expressive framework has not been tackled before. Our approach combines and extends previous work done separately for constraint logic programming and lazy functional programming languages. Diagnosis can be started whenever a user finds that the set of computed answers for a given goal with finite search space misses some expected solution w.r.t. an intended interpretation of the program, that provides a declarative description of its expected behavior. Diagnosis proceeds by exploring a proof tree, that provides a declarative view of the answer-collection process performed by the computation, and it ends up with the detection of some function definition in the program that is incomplete ...

• Type: Conference
• Year: 2008
• Where: FLOPS
• Authors: Rafael Caballero, Mario Rodríguez-Artalejo, Rafael del Vado Vírseda
• Keywords: Automated Reasoning, Computed Answers, Declarative Diagnosis, FLOPS 2008, Intended Interpretation