code: function Field(fieldOptions = {}) {
      return function (target, key) {
          let schema = MongoSchemaRegistry_1.MongoSchemaRegistry.getSchema(target.constructor.name);
          if (!schema) {
              schema = new MongoSchema_1.MongoSchema(target.constructor);
              MongoSchemaRegistry_1.MongoSchemaRegistry.register(target.constructor.name, schema);
          }
          fieldOptions.relationType = MongoSchema_1.ERelationType.None;
          schema.addField(key, (type) => {
              return fieldOptions.type || Reflect.getMetadata("design:type", target, key).name;
          }, fieldOptions);
      };
  }
docs: field tells