description: An expression that provides an alternative definition of the content of the value set in some form that is not computable - e.g instructions that could only be followed by a human. package_name: hl7.fhir.r5.examples derivation: constraint name: rules-text type: Extension elements: extension: {index: 0} url: pattern: {type: Uri, value: 'http://hl7.org/fhir/StructureDefinition/valueset-rules-text'} index: 1 value: choices: [valueMarkdown] index: 3 valueMarkdown: {type: markdown, choiceOf: value, index: 4} package_version: 4.5.0 extensions: {} class: extension kind: complex-type url: http://hl7.org/fhir/StructureDefinition/valueset-rules-text base: http://hl7.org/fhir/StructureDefinition/Extension version: 4.5.0 required: [valueMarkdown, value]