<?xml version=“1.0” encoding=“UTF-8”?> <SearchParameter xmlns=“hl7.org/fhir”>

      <id value="filter"/>
      <meta>
  <security>
    <system value="http://terminology.hl7.org/CodeSystem/v3-ActReason"/>
    <code value="HTEST"/>
    <display value="test health data"/>
  </security>
</meta>
<url value="http://hl7.org/fhir/SearchParameter/filter"/>
      <version value="1"/>
      <name value="FilterSearchParameter"/>
      <status value="draft"/>
      <experimental value="false"/>
      <date value="2018-07-26"/>
      <publisher value="Health Level Seven International (FHIR Infrastructure)"/>
      <contact>
              <name value="FHIR Project"/>
              <telecom>
                      <system value="url"/>
                      <value value="http://hl7.org/fhir"/>
              </telecom>
      </contact>
      <description value="This is the formal declaration for the _filter parameter, documented at [http://hl7.org/fhir/search_filter.html](http://hl7.org/fhir/search_filter.html)"/>

      <!--    this is the canonical definition for the _id search parameter     -->
      <purpose value="Support combination searches when the simple name=value basis of search cannot express what is required"/>
      <code value="_filter"/>
      <base value="Resource"/><!--   all resources   -->
      <type value="special"/>

</SearchParameter>