proposition: Lemma inf_itvcc x y : x <= y -> inf `[x, y] = x.
proof: Proof. by move=> *; rewrite inf_itv. Qed.
imports: mathcomp(all_ssreflect ssralg ssrnum ssrint interval) mathcomp(finmap fingroup perm rat) mathcomp(mathcomp_extra boolp classical_sets functions) HB(structures) reals ereal signed topology normedtype sequences