<INTERFACE> The <CD/ListSetFn/ functor <SEEALSO> <SIGREF/ORD_KEY/ <SIGREF/ORD_SET/ <FCTREF/BinarySetFn/ <FCTREF/SplaySetFn/ <SIGREF/ORD_MAP/ </SEEALSO> <PP> The <FCTREF NOLINK/ListSetFn/ functor implements applicative sets on an ordered type. It uses a sorted list representation. <ID/K/<ID>ORD_KEY</ID> <ID>ORD_SET <PP> Note that adding an element to a set that already contains such an element (in the sense that both elements are considered equal by the comparison function) causes the current element to be replaced by the new one. </INTERFACE>