whereKey<R> method
permite buscar mediante la comparacion con ula lista especificada */
Implementation
List<T> whereKey<R>(List<String> key, Map<String, dynamic> find) {
return _data.where((detail) {
for (var k in key) {
if (!detail.memberMap.containsKey(k)) return false;
if (detail.memberMap[k] is! Data) return false;
if ((detail.memberMap[k] as Data).value != find[k]) return false;
}
return true;
}).toList();
}