{
  "resourceType" : "SearchParameter",
  "id" : "codesystem-extensions-CodeSystem-effective",
  "url" : "http://hl7.org/fhir/SearchParameter/codesystem-extensions-CodeSystem-effective",
  "version" : "4.5.0",
  "name" : "effective",
  "status" : "draft",
  "experimental" : true,
  "description" : "Optional Extensions Element",
  "code" : "effective",
  "type" : "date",
  "xpath" : "f:CodeSystem/f:extension[@url='http://hl7.org/fhir/StructureDefinition/codesystem-effectiveDate'] | /f:#effectiveDate",
  "xpathUsage" : "normal"
}