<StructureDefinition xmlns="http://hl7.org/fhir">
  <meta>
    <lastUpdated value="2021-02-09T12:09:40.734+00:00" />
  </meta>
  <url value="http://example.org/fhir/StructureDefinition/SearchParameter" />
  <name value="SearchParameter" />
  <status value="draft" />
  <description value="used to capture paramters to be used in a EPIC search" />
  <fhirVersion value="4.0.1" />
  <mapping>
    <identity value="rim" />
    <uri value="http://hl7.org/v3" />
    <name value="RIM Mapping" />
  </mapping>
  <kind value="complex-type" />
  <abstract value="false" />
  <context>
    <type value="element" />
    <expression value="CommunicationRequest" />
  </context>
  <type value="Extension" />
  <baseDefinition value="http://hl7.org/fhir/StructureDefinition/Extension" />
  <derivation value="constraint" />
  <differential>
    <element id="Extension.url">
      <path value="Extension.url" />
      <fixedUri value="http://example.org/fhir/StructureDefinition/SearchParameter" />
    </element>
    <element id="Extension.value[x]">
      <path value="Extension.value[x]" />
      <type>
        <code value="Coding" />
      </type>
    </element>
    <element id="Extension.value[x].system">
      <path value="Extension.value[x].system" />
      <fixedUri value="http://hl7.org/fhir/resource-types" />
    </element>
    <element id="Extension.value[x].version">
      <path value="Extension.value[x].version" />
      <max value="0" />
    </element>
    <element id="Extension.value[x].code">
      <path value="Extension.value[x].code" />
      <binding>
        <strength value="required" />
        <description value="fhir resource types" />
        <valueSet value="http://hl7.org/fhir/ValueSet/resource-types" />
      </binding>
    </element>
    <element id="Extension.value[x].display">
      <path value="Extension.value[x].display" />
      <max value="0" />
    </element>
    <element id="Extension.value[x].userSelected">
      <path value="Extension.value[x].userSelected" />
      <max value="0" />
    </element>
  </differential>
</StructureDefinition>