proposition: Lemma gt0F x : unify_r <=0 cond -> x0 < x%:num :> T = false.
proof: Proof. by move=> ?; rewrite le_gtF//; apply: le0. Qed.
imports: HB(structures) Coq(ssreflect ssrfun ssrbool) mathcomp(ssrnat eqtype choice order ssralg ssrnum ssrint) mathcomp(mathcomp_extra)