description: This Extension profile represents a US Public Health Alternative Expression. package_name: hl7.fhir.us.ph-library derivation: constraint name: USPublicHealthAlternativeExpressionExtension type: Extension elements: extension: {index: 0} url: pattern: {type: uri, value: 'http://hl7.org/fhir/us/ph-library/StructureDefinition/us-ph-alternative-expression-extension'} type: uri index: 1 value: choices: [] index: 3 slicing: rules: open ordered: false discriminator: - {path: $this, type: type} min: null slices: valueExpression: match: {} schema: choices: [valueExpression] index: 5 min: 0 max: 1 valueExpression: type: Expression choiceOf: value index: 6 slicing: slices: valueExpression: match: {} schema: {type: Expression, choiceOf: value, index: 6} min: 0 max: 1 package_version: 2.0.0-ballot extensions: {} class: extension kind: complex-type url: http://hl7.org/fhir/us/ph-library/StructureDefinition/us-ph-alternative-expression-extension base: http://hl7.org/fhir/StructureDefinition/Extension version: 2.0.0-ballot