description: Marks the element or a set of sub-elements as optional - they do not need to be present package_name: hl7.fhir.uv.tools.r5 derivation: constraint name: MatchetypeOptionalFlag type: Extension elements: extension: {index: 0} url: pattern: {type: Uri, value: 'http://hl7.org/fhir/tools/StructureDefinition/matchetype-optional'} index: 1 value: choices: [valueString, valueBoolean] index: 3 valueString: {type: string, choiceOf: value, index: 4} valueBoolean: {type: boolean, choiceOf: value, index: 5} package_version: 0.4.0 extensions: {} class: extension kind: complex-type url: http://hl7.org/fhir/tools/StructureDefinition/matchetype-optional base: http://hl7.org/fhir/StructureDefinition/Extension version: 0.4.0 required: [valueString, value, valueBoolean]