<status value="active" /> <experimental value="false" /> <date value="2019" /> <publisher value="Chris Grenz" /> <contact> <telecom> <system value="email" /> <value value="chris.grenz@thoughtworks.com" /> </telecom> </contact> <description value="Simple boolean extension." /> <copyright value="(c)2019 Chris Grenz into public domain" /> <fhirVersion value="4.0.0" /> <kind value="complex-type" /> <abstract value="false" /> <context> <type value="element" /> <expression value="Patient" /> </context> <type value="Extension" /> <baseDefinition value="http://hl7.org/fhir/StructureDefinition/Extension" /> <derivation value="constraint" /> <differential> <element id="Extension"> <path value="Extension" /> </element> <element id="Extension.url"> <path value="Extension.url" /> <fixedUri value="http://example.com/fhir/StructureDefinition/patient-donotcall" /> </element> <element id="Extension.value[x]"> <path value="Extension.value[x]" /> <type> <code value="boolean" /> </type> </element> </differential> </StructureDefinition>