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• Content
• Detailed Descriptions
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Extension: system

URL for this extension:

http://hl7.org/fhir/StructureDefinition/valueset-system

Status: draft. Extension maintained by: HL7

Allows a direct reference to the code system for FHIR query.

Context of Use: Use on Element ID ValueSet.compose.include.system

Extension Content

• Summary
• Full Structure
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• JSON
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Summary

Name	Flags	Card.	Type	Description & Constraints
system		0..1	canonical(CodeSystem)	URL = http://hl7.org/fhir/StructureDefinition/valueset-system system: Allows a direct reference to the code system for FHIR query. Use on Element ID ValueSet.compose.include.system
Documentation for this format

Full Structure

Name	Flags	Card.	Type	Description & Constraints
extension		0..1	Extension	URL = http://hl7.org/fhir/StructureDefinition/valueset-system system: Allows a direct reference to the code system for FHIR query. Use on Element ID ValueSet.compose.include.system
extension		0..0
url		1..1	uri	"http://hl7.org/fhir/StructureDefinition/valueset-system"
value[x]		1..1	canonical(CodeSystem)	Value of extension
Documentation for this format

XML Template

<!-- system -->

<extension xmlns="http://hl7.org/fhir"
     url="http://hl7.org/fhir/StructureDefinition/valueset-system" >
  <!-- from Element: extension -->
 <valueCanonical value="[canonical]"/><!--  1..1 Value of extension -->
</extension>

JSON Template

{ // system
  // from Element: extension
    "extension" : [ //  sliced by value:url  in the specified order, Open ]
    "url" : "http://hl7.org/fhir/StructureDefinition/valueset-system", // R! 
    "valueCanonical" : "<canonical>" // C? R! Value of extension
  }

Summary

Name	Flags	Card.	Type	Description & Constraints
system		0..1	canonical(CodeSystem)	URL = http://hl7.org/fhir/StructureDefinition/valueset-system system: Allows a direct reference to the code system for FHIR query. Use on Element ID ValueSet.compose.include.system
Documentation for this format

Full Structure

Name	Flags	Card.	Type	Description & Constraints
extension		0..1	Extension	URL = http://hl7.org/fhir/StructureDefinition/valueset-system system: Allows a direct reference to the code system for FHIR query. Use on Element ID ValueSet.compose.include.system
extension		0..0
url		1..1	uri	"http://hl7.org/fhir/StructureDefinition/valueset-system"
value[x]		1..1	canonical(CodeSystem)	Value of extension
Documentation for this format

XML Template

<!-- system -->

<extension xmlns="http://hl7.org/fhir"
     url="http://hl7.org/fhir/StructureDefinition/valueset-system" >
  <!-- from Element: extension -->
 <valueCanonical value="[canonical]"/><!--  1..1 Value of extension -->
</extension>

JSON Template

{ // system
  // from Element: extension
    "extension" : [ //  sliced by value:url  in the specified order, Open ]
    "url" : "http://hl7.org/fhir/StructureDefinition/valueset-system", // R! 
    "valueCanonical" : "<canonical>" // C? R! Value of extension
  }

Constraints

• ele-1: All FHIR elements must have a @value or children unless an empty Parameters resource (xpath: @value|f:*|h:div|self::f:Parameters)
• ext-1: Must have either extensions or value[x], not both (xpath: exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')]))
• ele-1: On Extension.extension: All FHIR elements must have a @value or children (xpath on Extension.extension: @value|f:*|h:div)
• ext-1: On Extension.extension: Must have either extensions or value[x], not both (xpath on Extension.extension: exists(f:extension)!=exists(f:*[starts-with(local-name(.), "value")]))
• ele-1: On Extension.value[x]: All FHIR elements must have a @value or children (xpath on Extension.value[x]: @value|f:*|h:div)