proposition: Lemma FL_refl s : s \in FL s.
proof: Proof. case: s => [|||[]] /=; by fset_nocut. Qed.
imports: Relations Lia Setoid Morphisms mathcomp(all_ssreflect) CompDecModal.libs(edone bcase fset base modular_hilbert sltype rewrite_inequality fset_tac)