{"abstract":false,"baseDefinition":"http://hl7.org/fhir/StructureDefinition/uri","contact":[{"telecom":[{"system":"url","value":"http://hl7.org/fhir"}]}],"date":"2019-12-31T21:03:40+11:00","derivation":"specialization","description":"Base StructureDefinition for canonical type: A URI that is a reference to a canonical URL on a FHIR resource","differential":{"element":[{"comment":"see [Canonical References](references.html#canonical)","definition":"A URI that is a reference to a canonical URL on a FHIR resource","id":"canonical","max":"*","min":0,"path":"canonical","short":"Primitive Type canonical"},{"definition":"Primitive value for canonical","id":"canonical.value","max":"1","min":0,"path":"canonical.value","representation":["xmlAttr"],"short":"Primitive value for canonical","type":[{"code":"http://hl7.org/fhirpath/System.String","extension":[{"url":"http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type","valueUri":"canonical"},{"url":"http://hl7.org/fhir/StructureDefinition/regex","valueString":"\\S*"}]}]}]},"extension":[{"url":"http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status","valueCode":"normative"},{"url":"http://hl7.org/fhir/StructureDefinition/structuredefinition-normative-version","valueCode":"4.0.0"}],"fhirVersion":"4.2.0","id":"canonical","kind":"primitive-type","name":"canonical","publisher":"HL7 FHIR Standard","resourceType":"StructureDefinition","snapshot":{"element":[{"base":{"max":"*","min":0,"path":"canonical"},"comment":"see [Canonical References](references.html#canonical)","constraint":[{"expression":"hasValue() or (children().count() > id.count())","human":"All FHIR elements must have a @value or children","key":"ele-1","severity":"error","source":"Element","xpath":"@value|f:*|h:div"}],"definition":"A URI that is a reference to a canonical URL on a FHIR resource","id":"canonical","isModifier":false,"isSummary":false,"max":"*","min":0,"path":"canonical","short":"Primitive Type canonical"},{"base":{"max":"1","min":0,"path":"Element.id"},"definition":"unique id for the element within a resource (for internal references)","id":"canonical.id","isModifier":false,"isSummary":false,"max":"1","min":0,"path":"canonical.id","representation":["xmlAttr"],"short":"xml:id (or equivalent in JSON)","type":[{"code":"http://hl7.org/fhirpath/System.String","extension":[{"url":"http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type","valueUri":"string"}]}]},{"alias":["extensions","user content"],"base":{"max":"*","min":0,"path":"Element.extension"},"comment":"There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions.  The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.","constraint":[{"expression":"hasValue() or (children().count() > id.count())","human":"All FHIR elements must have a @value or children","key":"ele-1","severity":"error","source":"Element","xpath":"@value|f:*|h:div"},{"expression":"extension.exists() != value.exists()","human":"Must have either extensions or value[x], not both","key":"ext-1","severity":"error","source":"Extension","xpath":"exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])"}],"definition":"May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance  applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.","id":"canonical.extension","isModifier":false,"isSummary":false,"max":"*","min":0,"path":"canonical.extension","short":"Additional content defined by implementations","type":[{"code":"Extension"}]},{"base":{"max":"1","min":0,"path":"uri.value"},"definition":"Primitive value for canonical","id":"canonical.value","isModifier":false,"isSummary":false,"max":"1","min":0,"path":"canonical.value","representation":["xmlAttr"],"short":"Primitive value for canonical","type":[{"code":"http://hl7.org/fhirpath/System.String","extension":[{"url":"http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type","valueUri":"string"},{"url":"http://hl7.org/fhir/StructureDefinition/regex","valueString":"\\S*"}]}]}]},"status":"active","text":{"div":"<div xmlns=\"http://www.w3.org/1999/xhtml\">to do</div>","status":"generated"},"type":"canonical","url":"http://hl7.org/fhir/StructureDefinition/canonical","version":"4.2.0"}