Availability:built-in
[det]nb_set_dict(+Key, 
!Dict, +Value)Destructively update the value associated with Key in Dict 
to a copy of Value. The update is not undone on 
backtracking. This predicate raises an existence error if Key 
does not appear in
Dict. The update semantics are equivalent to nb_setarg/3 
and
nb_setval/2.