disjoint? cannot decide
disjoint? cannot decide (and Boolean (rte (:cat String :sigma))) vs Boolean -- assuming not disjoint
disjoint? cannot decide (and (rte (:cat String :sigma)) String) vs String -- assuming not disjoint
disjoint? cannot decide (and Boolean (rte (:cat String :sigma))) vs Boolean -- assuming not disjoint
disjoint? cannot decide (and (rte (:cat String :sigma)) String) vs String -- assuming not disjoint