proposition: Lemma measurable_subring : (d.-measurable : set (set T)) `<=` d.-ring.-measurable.
proof: Proof. by rewrite /measurable => X Xmeas /= M /= [_]; apply. Qed.
imports: mathcomp(all_ssreflect all_algebra finmap) mathcomp(mathcomp_extra boolp classical_sets functions) mathcomp(cardinality fsbigop ) reals ereal signed topology normedtype sequences esum numfun HB(structures)