description: Tracks which structure first defined an extension found in the snapshot package_name: hl7.fhir.uv.tools derivation: constraint name: ExtensionSnapshotSource type: Extension elements: extension: {index: 0} url: pattern: {type: uri, value: 'http://hl7.org/fhir/tools/StructureDefinition/snapshot-source'} type: uri index: 1 value: choices: [valueCanonical] index: 3 valueCanonical: {type: canonical, choiceOf: value, index: 4} package_version: 0.6.0 extensions: {} class: extension kind: complex-type url: http://hl7.org/fhir/tools/StructureDefinition/snapshot-source base: http://hl7.org/fhir/StructureDefinition/Extension version: 0.6.0 required: [value, valueCanonical]