proposition: Lemma card_inter_le_l : forall A (E F:set A), finite E -> card (E \n F) <= card E.
proof: Proof. Proof using. intros. applys~ card_le_of_incl. set_prove. Qed.
imports: Coq.Classes.Morphisms TLC(LibTactics LibLogic LibReflect LibList LibOperation LibMonoid LibInt LibNat LibEpsilon LibRelation LibMin)