proposition: Lemma erestrict_set0 f : f \_ set0 = cst 0.
proof: Proof. by rewrite patch_set0. Qed.
imports: HB(structures) mathcomp(all_ssreflect ssralg ssrnum ssrint interval finmap) mathcomp(mathcomp_extra boolp classical_sets fsbigop) mathcomp(functions cardinality set_interval) signed reals ereal topology normedtype sequences