description: This can be a unit designator, such as apartment number, suite number, or floor. There may be several unit designators in an address (e.g., \"3rd floor, Appt. 342\"). This can also be a designator pointing away from the location, rather than specifying a smaller location within some larger one (e.g., Dutch \"t.o.\" means \"opposite to\" for house boats located across the street facing houses). package_name: hl7.fhir.uv.extensions.r4 derivation: constraint name: ADXPAdditionalLocator type: Extension elements: extension: {index: 0} url: pattern: {type: Uri, value: 'http://hl7.org/fhir/StructureDefinition/iso21090-ADXP-additionalLocator'} index: 1 value: choices: [valueString] index: 3 valueString: {type: string, choiceOf: value, index: 4} package_version: 5.1.0 extensions: {} class: extension kind: complex-type url: http://hl7.org/fhir/StructureDefinition/iso21090-ADXP-additionalLocator base: http://hl7.org/fhir/StructureDefinition/Extension version: 5.1.0 required: [valueString, value]