Inheritance: Datatype_anySimpleType
 internal XmlSchemaDatatype DeriveByList(int minSize, XmlSchemaType schemaType) {
     if (variety == XmlSchemaDatatypeVariety.List) {
         throw new XmlSchemaException(Res.Sch_ListFromNonatomic, string.Empty);
     }
     else if (variety == XmlSchemaDatatypeVariety.Union && !((Datatype_union)this).HasAtomicMembers()) {
         throw new XmlSchemaException(Res.Sch_ListFromNonatomic, string.Empty);
     }
     DatatypeImplementation dt = new Datatype_List(this, minSize);
     dt.variety = XmlSchemaDatatypeVariety.List;
     dt.restriction = null;
     dt.baseType = c_anySimpleType; //Base type of a union is anySimpleType
     dt.parentSchemaType = schemaType;
     return dt;
 }