proposition: Lemma prune_D0 : D0 (S `|` T).
proof: Proof. move => C H. suff: C \in S0 by rewrite !inE; bcase. case/fsetUP : H; by [move/(subP prune_sub)| case/sepP]. Qed.
imports: Relations Lia mathcomp.ssreflect.ssreflect mathcomp(all_ssreflect) CompDecModal.libs(edone bcase fset base modular_hilbert sltype) CompDecModal.Kstar(Kstar_def demo hilbert_ref gen_def)