Section ListDenoteSortUniqPreds.
Context {A B : Type}.
Variables (f : A -> pred B) (b : pred B).
Variable (cmp : A -> A -> comparison).
Variable (Hcmp : forall x y, Eq = cmp x y -> x = y).
Local Hint Resolve (@interS B) (@interA B) (@unS B) (@unA B).

Lemma listd_sort_uniq_un l :
listd f un b (rsort_uniq cmp l) = listd f un b l.