RELFUN

Appeared in Volume 9/4, November 1996

RELFUN is a LP language with call-by-value (eager) expressions of non-deterministic, non-ground functions. Clauses are 'hornish', succeeding with true, or 'footed', returning values. They define operations (relations and functions) permitting apply-reducible higher-order syntax with arbitrary terms as operators.

Finite domains and exclusions, as well as sorts, are first-class citizens build into unification.

Extensions include single-cut clauses and relational-functional primitives such as a value-returning tupof.

Versions of RELFUN are used in the hybrid COLAB shell and in VEGA's Declarative Representation Language.

For more details, contact:

Harald Boley and Michael Sintek
Email: sintek@dfki.uni-kl.de
URL: http://www.dfki.uni-kl.de/vega/relfun.html