proposition: Lemma fdisjointWr A B C : A `<=` B -> [disjoint C & B] -> [disjoint C & A].
proof: Proof. by rewrite ![[disjoint C & _]]fdisjoint_sym; apply: fdisjointWl. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrnat eqtype ssrfun seq) mathcomp(choice path finset finfun fintype bigop)