proposition: Lemma subset_measure0 : A `<=` B -> mu B = 0 -> mu A = 0.
proof: Proof. by move=> ? B0; apply/eqP; rewrite -measure_le0 -B0 le_measure ?inE. 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)