proposition: Lemma consec_prev (ks : seq A) x y z : uniq ks -> consec ks x y -> z <[ks] y -> z <=[ks] x.
proof: Proof. by move=>U; case/(consecP_inlt _ _ U)=>X E N; rewrite -E // (slt_memE N). Qed.
imports: Coq(ssreflect ssrbool ssrfun) mathcomp(ssrnat eqtype seq path interval order) pcm(options prelude ordtype seqext slice useqord uslice)