unctional predicates</p>
<p>    A specialization of #$Predicate whose instances are those predicates that are functional in at least one argument-place (see #$functionalInArgs and #$singleEntryFormatInArgs). That is, given any sequence of legal arguments placed in such a predicate's other argument positions, there is at most one argument such that, when it is placed in the predicate's functional position, the resulting formula is true. More precisely: Suppose PRED is an N-ary instance of #$FunctionalPred