description: null package_name: se.electronichealth.fhir.nll.r4 derivation: constraint name: NLLPeriod type: Extension elements: extension: {index: 0} url: pattern: {type: Uri, value: 'http://electronichealth.se/fhir/StructureDefinition/NLLPeriod'} index: 1 value: choices: [valuePeriod] index: 3 valuePeriod: {type: Period, choiceOf: value, index: 4} package_version: 1.0.2-alpha extensions: {} class: extension kind: complex-type url: http://electronichealth.se/fhir/StructureDefinition/NLLPeriod base: http://hl7.org/fhir/StructureDefinition/Extension version: 1.0.0