Heap and Priority with its priority value. min_of_heap/5Gets the two minimum-priority elements from Heap. singleton_heap/3True if Heap is a heap with the single element Priority-Key.

F.2.22 library(increval)

incr_directly_depends/2	True if Goal1 depends on Goal2 in the IDG.
incr_invalid_subgoals/1	List is a sorted list (set) of the incremental subgoals that are currently invalid.
incr_invalidate_call/1	This is the XSB name, but the manual says incr_invalidate_calls/1 and the comment with the code suggests this is misnamed.
incr_invalidate_calls/1	Invalidate all tables for subgoals of Goal as well as tables that are affected by these.
incr_is_invalid/1	True when Subgoal's table is marked as invalid.
incr_propagate_calls/1	Activate the monotonic answer propagation similarly to when a new fact is asserted for a monotonic dynamic predicate.
incr_table_update/0	Updated all invalid tables.
incr_tr