description: This specifies the definition for a parameter if needed. This is useful for communicating the type of a parameter when the parameter has no value. package_name: hl7.fhir.uv.extensions.r4 derivation: constraint name: ParametersDefinition type: Extension elements: extension: {index: 0} url: pattern: {type: uri, value: 'http://hl7.org/fhir/StructureDefinition/parameters-definition'} type: uri index: 1 value: choices: [valueParameterDefinition] index: 3 valueParameterDefinition: {type: ParameterDefinition, choiceOf: value, index: 4} package_version: 5.3.0-ballot-tc extensions: {} class: extension kind: complex-type url: http://hl7.org/fhir/StructureDefinition/parameters-definition base: http://hl7.org/fhir/StructureDefinition/Extension version: 5.3.0-ballot-tc required: [value, valueParameterDefinition]