Declarative Programming with Real Constraints

. We present a declarative language -- CFLP (R) -- which enhances functional logic programming with constraint solving capabilities. CFLP (R) features: polymorphic types, nondeterministic functions, lazy evaluation, higher order (even logic) computations, arithmetical constraints over real numbers and disequality constraints over syntactic terms. The features of the language are shown by means of examples, attempting to demonstrate the interest of CFLP (R). The execution mechanism of the language results of a simple combination of lazy narrowing (with a sophisticated strategy, as realized in up to date functional logic languages) and constraint solving. The language has been implemented by means of translation of source programs into a Prolog system supporting real constraint solving. This shows the practicability of the proposal. 1 Introduction Constraints play a central role in present days research, development and application of logic programming (LP) languages (see [15] for a sur..