Rafael del Vado Vírseda

A lazy narrowing calculus for declarative constraint programming

The new generic scheme CFLP (D) has been recently proposed in [24] as a logical and semantic framework for lazy constraint functional logic programming over a parametrically given constraint domain D. In this paper we extend such framework with a suitable operational semantics, which relies on a new constrained lazy narrowing calculus for goal solving parameterized by a constraint solver over the given domain D. This new calculus is sound and strongly complete w.r.t. the declarative semantics of CFLP (D)programs, which was formalized in [24] by means of a Constraint Rewriting Logic CRWL (D).

A demand-driven narrowing calculus with overlapping definitional trees

We propose a demand-driven conditional narrowing calculus in which a variant of definitional trees [2] is used to efficiently control the narrowing strategy. This calculus is sound and strongly complete w.r.t. Constructor-based ReWriting Logic (CRWL) semantics [7] for a wide class of constructor-based conditional term rewriting systems. The calculus mantains the optimality properties of the needed narrowing strategy [5]. Moreover, the treatment of strict equality as a primitive rather than a defined function symbol, leads to an improved behaviour w.r.t. needed narrowing.

Declarative constraint programming with definitional trees

The new generic scheme CFLP(

A new generic scheme for functional logic programming with constraints

mathcal{D}

Declarative diagnosis of missing answers in constraint functional-logic programming

) has been recently proposed in [14] as a logical and semantic framework for lazy Constraint Functional Logic Programming over a parametrically given constraint domain

Constraint Functional Logic Programming Revisited

mathcal{D}

A higher-order logical framework for the algorithmic debugging and verification of declarative programs

. Further, [15] presented a Constrained Lazy Narrowing Calculus

A higher-order demand-driven narrowing calculus with definitional trees

CLNC(mathcal{D})

Designing an efficient computation strategy in CFLP(FD) using definitional trees

as a convenient computation mechanism for solving goals for CFLP(

A visualization tool for tutoring the interactive learning of data structures and algorithmic schemes.

mathcal{D}