proposition: Lemma inf_itv a b x : (BSide b x < a)%O -> inf [set` Interval (BSide b x) a] = x.
proof: Proof. by case: a => [b' y|[]]; rewrite ?bnd_simp//= => /inf_itv_bounded->. 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