proposition: Lemma le_ninfty b : (b <= -oo) = (b == -oo).
proof: Proof. by case: b => // - []. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(div fintype bigop order ssralg finset fingroup) mathcomp(ssrnum)