FHIR IG Statistics: StructureDefinition/feature
Resources that use this resource
Resources that this resource uses
Examples of Use for Extension
Narrative
Note: links and images are rebased to the (stated) source
| Name | Flags | Card. | Type | Description & Constraints |
|---|
  Extension | | 0..* | Extension | Extension |
  extension | | 2..* | Extension | Extension |
 Slices for extension | | | | Content/Rules for all slices |
   extension:definition | S | 1..1 | Extension | Extension |
  extension | | 0..0 | | |
| url | | 1..1 | uri | "definition" |
  value[x] | | 1..1 | canonical(Feature Definition(1.0.0)) | Value of extension |
 extension:value | S | 1..1 | Extension | Extension |
 extension | | 0..0 | | |
| url | | 1..1 | uri | "value" |
| value[x] | | 1..1 | base64Binary, boolean, canonical(), code, date, dateTime, decimal, id, instant, integer, integer64, markdown, oid, positiveInt, string, time, unsignedInt, uri, url, uuid, Address, Age, Annotation, Attachment, CodeableConcept, CodeableReference(), Coding, ContactPoint, Count, Distance, Duration, HumanName, Identifier, Money, Period, Quantity, Range, Ratio, RatioRange, Reference(), SampledData, Signature, Timing, ContactDetail, DataRequirement, Expression, ParameterDefinition, RelatedArtifact, TriggerDefinition, UsageContext, Availability, ExtendedContactDetail, Dosage, Meta | Value of extension |
| url | | 1..1 | uri | "http://hl7.org/fhir/uv/application-feature/StructureDefinition/feature" |
 value[x] | | 0..0 | | |
Documentation for this format |
Source
{
"resourceType": "StructureDefinition",
"id": "feature",
"text": {
"status": "extensions",
"div": "<!-- snip (see above) -->"
},
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-type-characteristics",
"valueCode": "can-bind"
},
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-wg",
"valueCode": "fhir"
},
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm",
"valueInteger": 1,
"_valueInteger": {
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-conformance-derivedFrom",
"valueCanonical": "http://hl7.org/fhir/uv/application-feature/ImplementationGuide/hl7.fhir.uv.application-feature"
}
]
}
},
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status",
"valueCode": "trial-use",
"_valueCode": {
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-conformance-derivedFrom",
"valueCanonical": "http://hl7.org/fhir/uv/application-feature/ImplementationGuide/hl7.fhir.uv.application-feature"
}
]
}
}
],
"url": "http://hl7.org/fhir/uv/application-feature/StructureDefinition/feature",
"version": "1.0.0",
"name": "Feature",
"status": "active",
"date": "2025-05-15T09:57:57+00:00",
"publisher": "HL7 International / FHIR Infrastructure",
"contact": [
{
"name": "HL7 International / FHIR Infrastructure",
"telecom": [
{
"system": "url",
"value": "http://www.hl7.org/Special/committees/fiwg"
}
]
}
],
"description": "This extension documents the features of a system using code/value pairs",
"jurisdiction": [
{
"coding": [
{
"system": "http://unstats.un.org/unsd/methods/m49/m49.htm",
"code": "001",
"display": "World"
}
]
}
],
"fhirVersion": "5.0.0",
"mapping": [
{
"identity": "rim",
"uri": "http://hl7.org/v3",
"name": "RIM Mapping"
}
],
"kind": "complex-type",
"abstract": false,
"context": [
{
"type": "element",
"expression": "Element"
}
],
"type": "Extension",
"baseDefinition": "http://hl7.org/fhir/StructureDefinition/Extension",
"derivation": "constraint",
"snapshot": {
"extension": [
{
"url": "http://hl7.org/fhir/tools/StructureDefinition/snapshot-base-version",
"valueString": "5.0.0"
}
],
"element": [
{
"id": "Extension",
"path": "Extension",
"short": "Extension",
"definition": "This extension documents the features of a system using code/value pairs",
"min": 0,
"max": "*",
"base": {
"path": "Extension",
"min": 0,
"max": "*"
},
"constraint": [
{
"key": "ele-1",
"severity": "error",
"human": "All FHIR elements must have a @value or children",
"expression": "hasValue() or (children().count() > id.count())",
"source": "http://hl7.org/fhir/StructureDefinition/Element"
},
{
"key": "ext-1",
"severity": "error",
"human": "Must have either extensions or value[x], not both",
"expression": "extension.exists() != value.exists()",
"source": "http://hl7.org/fhir/StructureDefinition/Extension"
}
],
"isModifier": false
},
{
"id": "Extension.id",
"path": "Extension.id",
"representation": [
"xmlAttr"
],
"short": "Unique id for inter-element referencing",
"definition": "Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
"min": 0,
"max": "1",
"base": {
"path": "Element.id",
"min": 0,
"max": "1"
},
"type": [
{
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
"valueUrl": "id"
}
],
"code": "http://hl7.org/fhirpath/System.String"
}
],
"condition": [
"ele-1"
],
"isModifier": false,
"isSummary": false,
"mapping": [
{
"identity": "rim",
"map": "n/a"
}
]
},
{
"id": "Extension.extension",
"path": "Extension.extension",
"slicing": {
"discriminator": [
{
"type": "value",
"path": "url"
}
],
"description": "Extensions are always sliced by (at least) url",
"rules": "open"
},
"short": "Extension",
"definition": "An Extension",
"min": 2,
"max": "*",
"base": {
"path": "Element.extension",
"min": 0,
"max": "*"
},
"type": [
{
"code": "Extension"
}
],
"constraint": [
{
"key": "ele-1",
"severity": "error",
"human": "All FHIR elements must have a @value or children",
"expression": "hasValue() or (children().count() > id.count())",
"source": "http://hl7.org/fhir/StructureDefinition/Element"
},
{
"key": "ext-1",
"severity": "error",
"human": "Must have either extensions or value[x], not both",
"expression": "extension.exists() != value.exists()",
"source": "http://hl7.org/fhir/StructureDefinition/Extension"
}
],
"isModifier": false,
"isSummary": false
},
{
"id": "Extension.extension:definition",
"path": "Extension.extension",
"sliceName": "definition",
"short": "Extension",
"definition": "An Extension",
"min": 1,
"max": "1",
"base": {
"path": "Element.extension",
"min": 0,
"max": "*"
},
"type": [
{
"code": "Extension"
}
],
"constraint": [
{
"key": "ele-1",
"severity": "error",
"human": "All FHIR elements must have a @value or children",
"expression": "hasValue() or (children().count() > id.count())",
"source": "http://hl7.org/fhir/StructureDefinition/Element"
},
{
"key": "ext-1",
"severity": "error",
"human": "Must have either extensions or value[x], not both",
"expression": "extension.exists() != value.exists()",
"source": "http://hl7.org/fhir/StructureDefinition/Extension"
}
],
"mustSupport": true,
"isModifier": false,
"isSummary": false
},
{
"id": "Extension.extension:definition.id",
"path": "Extension.extension.id",
"representation": [
"xmlAttr"
],
"short": "Unique id for inter-element referencing",
"definition": "Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
"min": 0,
"max": "1",
"base": {
"path": "Element.id",
"min": 0,
"max": "1"
},
"type": [
{
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
"valueUrl": "id"
}
],
"code": "http://hl7.org/fhirpath/System.String"
}
],
"condition": [
"ele-1"
],
"isModifier": false,
"isSummary": false,
"mapping": [
{
"identity": "rim",
"map": "n/a"
}
]
},
{
"id": "Extension.extension:definition.extension",
"path": "Extension.extension.extension",
"slicing": {
"discriminator": [
{
"type": "value",
"path": "url"
}
],
"description": "Extensions are always sliced by (at least) url",
"rules": "open"
},
"short": "Extension",
"definition": "An Extension",
"min": 0,
"max": "0",
"base": {
"path": "Element.extension",
"min": 0,
"max": "*"
},
"type": [
{
"code": "Extension"
}
],
"constraint": [
{
"key": "ele-1",
"severity": "error",
"human": "All FHIR elements must have a @value or children",
"expression": "hasValue() or (children().count() > id.count())",
"source": "http://hl7.org/fhir/StructureDefinition/Element"
},
{
"key": "ext-1",
"severity": "error",
"human": "Must have either extensions or value[x], not both",
"expression": "extension.exists() != value.exists()",
"source": "http://hl7.org/fhir/StructureDefinition/Extension"
}
],
"isModifier": false,
"isSummary": false
},
{
"id": "Extension.extension:definition.url",
"path": "Extension.extension.url",
"representation": [
"xmlAttr"
],
"short": "identifies the meaning of the extension",
"definition": "Source of the definition for the extension code - a logical name or a URL.",
"comment": "The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.",
"min": 1,
"max": "1",
"base": {
"path": "Extension.url",
"min": 1,
"max": "1"
},
"type": [
{
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
"valueUrl": "uri"
}
],
"code": "http://hl7.org/fhirpath/System.String"
}
],
"fixedUri": "definition",
"isModifier": false,
"isSummary": false,
"mapping": [
{
"identity": "rim",
"map": "N/A"
}
]
},
{
"id": "Extension.extension:definition.value[x]",
"path": "Extension.extension.value[x]",
"short": "Value of extension",
"definition": "Value of extension - must be one of a constrained set of the data types (see [Extensibility](http://hl7.org/fhir/R5/extensibility.html) for a list).",
"min": 1,
"max": "1",
"base": {
"path": "Extension.value[x]",
"min": 0,
"max": "1"
},
"type": [
{
"code": "canonical",
"targetProfile": [
"http://hl7.org/fhir/uv/application-feature/StructureDefinition/FeatureDefinition|1.0.0"
]
}
],
"condition": [
"ext-1"
],
"constraint": [
{
"key": "ele-1",
"severity": "error",
"human": "All FHIR elements must have a @value or children",
"expression": "hasValue() or (children().count() > id.count())",
"source": "http://hl7.org/fhir/StructureDefinition/Element"
}
],
"isModifier": false,
"isSummary": false,
"mapping": [
{
"identity": "rim",
"map": "N/A"
}
]
},
{
"id": "Extension.extension:value",
"path": "Extension.extension",
"sliceName": "value",
"short": "Extension",
"definition": "An Extension",
"min": 1,
"max": "1",
"base": {
"path": "Element.extension",
"min": 0,
"max": "*"
},
"type": [
{
"code": "Extension"
}
],
"constraint": [
{
"key": "ele-1",
"severity": "error",
"human": "All FHIR elements must have a @value or children",
"expression": "hasValue() or (children().count() > id.count())",
"source": "http://hl7.org/fhir/StructureDefinition/Element"
},
{
"key": "ext-1",
"severity": "error",
"human": "Must have either extensions or value[x], not both",
"expression": "extension.exists() != value.exists()",
"source": "http://hl7.org/fhir/StructureDefinition/Extension"
}
],
"mustSupport": true,
"isModifier": false,
"isSummary": false
},
{
"id": "Extension.extension:value.id",
"path": "Extension.extension.id",
"representation": [
"xmlAttr"
],
"short": "Unique id for inter-element referencing",
"definition": "Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
"min": 0,
"max": "1",
"base": {
"path": "Element.id",
"min": 0,
"max": "1"
},
"type": [
{
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
"valueUrl": "id"
}
],
"code": "http://hl7.org/fhirpath/System.String"
}
],
"condition": [
"ele-1"
],
"isModifier": false,
"isSummary": false,
"mapping": [
{
"identity": "rim",
"map": "n/a"
}
]
},
{
"id": "Extension.extension:value.extension",
"path": "Extension.extension.extension",
"slicing": {
"discriminator": [
{
"type": "value",
"path": "url"
}
],
"description": "Extensions are always sliced by (at least) url",
"rules": "open"
},
"short": "Extension",
"definition": "An Extension",
"min": 0,
"max": "0",
"base": {
"path": "Element.extension",
"min": 0,
"max": "*"
},
"type": [
{
"code": "Extension"
}
],
"constraint": [
{
"key": "ele-1",
"severity": "error",
"human": "All FHIR elements must have a @value or children",
"expression": "hasValue() or (children().count() > id.count())",
"source": "http://hl7.org/fhir/StructureDefinition/Element"
},
{
"key": "ext-1",
"severity": "error",
"human": "Must have either extensions or value[x], not both",
"expression": "extension.exists() != value.exists()",
"source": "http://hl7.org/fhir/StructureDefinition/Extension"
}
],
"isModifier": false,
"isSummary": false
},
{
"id": "Extension.extension:value.url",
"path": "Extension.extension.url",
"representation": [
"xmlAttr"
],
"short": "identifies the meaning of the extension",
"definition": "Source of the definition for the extension code - a logical name or a URL.",
"comment": "The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.",
"min": 1,
"max": "1",
"base": {
"path": "Extension.url",
"min": 1,
"max": "1"
},
"type": [
{
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
"valueUrl": "uri"
}
],
"code": "http://hl7.org/fhirpath/System.String"
}
],
"fixedUri": "value",
"isModifier": false,
"isSummary": false,
"mapping": [
{
"identity": "rim",
"map": "N/A"
}
]
},
{
"id": "Extension.extension:value.value[x]",
"path": "Extension.extension.value[x]",
"short": "Value of extension",
"definition": "Value of extension - must be one of a constrained set of the data types (see [Extensibility](http://hl7.org/fhir/R5/extensibility.html) for a list).",
"min": 1,
"max": "1",
"base": {
"path": "Extension.value[x]",
"min": 0,
"max": "1"
},
"type": [
{
"code": "base64Binary"
},
{
"code": "boolean"
},
{
"code": "canonical"
},
{
"code": "code"
},
{
"code": "date"
},
{
"code": "dateTime"
},
{
"code": "decimal"
},
{
"code": "id"
},
{
"code": "instant"
},
{
"code": "integer"
},
{
"code": "integer64"
},
{
"code": "markdown"
},
{
"code": "oid"
},
{
"code": "positiveInt"
},
{
"code": "string"
},
{
"code": "time"
},
{
"code": "unsignedInt"
},
{
"code": "uri"
},
{
"code": "url"
},
{
"code": "uuid"
},
{
"code": "Address"
},
{
"code": "Age"
},
{
"code": "Annotation"
},
{
"code": "Attachment"
},
{
"code": "CodeableConcept"
},
{
"code": "CodeableReference"
},
{
"code": "Coding"
},
{
"code": "ContactPoint"
},
{
"code": "Count"
},
{
"code": "Distance"
},
{
"code": "Duration"
},
{
"code": "HumanName"
},
{
"code": "Identifier"
},
{
"code": "Money"
},
{
"code": "Period"
},
{
"code": "Quantity"
},
{
"code": "Range"
},
{
"code": "Ratio"
},
{
"code": "RatioRange"
},
{
"code": "Reference"
},
{
"code": "SampledData"
},
{
"code": "Signature"
},
{
"code": "Timing"
},
{
"code": "ContactDetail"
},
{
"code": "DataRequirement"
},
{
"code": "Expression"
},
{
"code": "ParameterDefinition"
},
{
"code": "RelatedArtifact"
},
{
"code": "TriggerDefinition"
},
{
"code": "UsageContext"
},
{
"code": "Availability"
},
{
"code": "ExtendedContactDetail"
},
{
"code": "Dosage"
},
{
"code": "Meta"
}
],
"condition": [
"ext-1"
],
"constraint": [
{
"key": "ele-1",
"severity": "error",
"human": "All FHIR elements must have a @value or children",
"expression": "hasValue() or (children().count() > id.count())",
"source": "http://hl7.org/fhir/StructureDefinition/Element"
}
],
"isModifier": false,
"isSummary": false,
"mapping": [
{
"identity": "rim",
"map": "N/A"
}
]
},
{
"id": "Extension.url",
"path": "Extension.url",
"representation": [
"xmlAttr"
],
"short": "identifies the meaning of the extension",
"definition": "Source of the definition for the extension code - a logical name or a URL.",
"comment": "The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.",
"min": 1,
"max": "1",
"base": {
"path": "Extension.url",
"min": 1,
"max": "1"
},
"type": [
{
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
"valueUrl": "uri"
}
],
"code": "http://hl7.org/fhirpath/System.String"
}
],
"fixedUri": "http://hl7.org/fhir/uv/application-feature/StructureDefinition/feature",
"isModifier": false,
"isSummary": false,
"mapping": [
{
"identity": "rim",
"map": "N/A"
}
]
},
{
"id": "Extension.value[x]",
"path": "Extension.value[x]",
"short": "Value of extension",
"definition": "Value of extension - must be one of a constrained set of the data types (see [Extensibility](http://hl7.org/fhir/R5/extensibility.html) for a list).",
"min": 0,
"max": "0",
"base": {
"path": "Extension.value[x]",
"min": 0,
"max": "1"
},
"type": [
{
"code": "base64Binary"
},
{
"code": "boolean"
},
{
"code": "canonical"
},
{
"code": "code"
},
{
"code": "date"
},
{
"code": "dateTime"
},
{
"code": "decimal"
},
{
"code": "id"
},
{
"code": "instant"
},
{
"code": "integer"
},
{
"code": "integer64"
},
{
"code": "markdown"
},
{
"code": "oid"
},
{
"code": "positiveInt"
},
{
"code": "string"
},
{
"code": "time"
},
{
"code": "unsignedInt"
},
{
"code": "uri"
},
{
"code": "url"
},
{
"code": "uuid"
},
{
"code": "Address"
},
{
"code": "Age"
},
{
"code": "Annotation"
},
{
"code": "Attachment"
},
{
"code": "CodeableConcept"
},
{
"code": "CodeableReference"
},
{
"code": "Coding"
},
{
"code": "ContactPoint"
},
{
"code": "Count"
},
{
"code": "Distance"
},
{
"code": "Duration"
},
{
"code": "HumanName"
},
{
"code": "Identifier"
},
{
"code": "Money"
},
{
"code": "Period"
},
{
"code": "Quantity"
},
{
"code": "Range"
},
{
"code": "Ratio"
},
{
"code": "RatioRange"
},
{
"code": "Reference"
},
{
"code": "SampledData"
},
{
"code": "Signature"
},
{
"code": "Timing"
},
{
"code": "ContactDetail"
},
{
"code": "DataRequirement"
},
{
"code": "Expression"
},
{
"code": "ParameterDefinition"
},
{
"code": "RelatedArtifact"
},
{
"code": "TriggerDefinition"
},
{
"code": "UsageContext"
},
{
"code": "Availability"
},
{
"code": "ExtendedContactDetail"
},
{
"code": "Dosage"
},
{
"code": "Meta"
}
],
"condition": [
"ext-1"
],
"constraint": [
{
"key": "ele-1",
"severity": "error",
"human": "All FHIR elements must have a @value or children",
"expression": "hasValue() or (children().count() > id.count())",
"source": "http://hl7.org/fhir/StructureDefinition/Element"
}
],
"isModifier": false,
"isSummary": false,
"mapping": [
{
"identity": "rim",
"map": "N/A"
}
]
}
]
},
"differential": {
"element": [
{
"id": "Extension",
"path": "Extension",
"definition": "This extension documents the features of a system using code/value pairs"
},
{
"id": "Extension.extension",
"path": "Extension.extension",
"min": 2
},
{
"id": "Extension.extension:definition",
"path": "Extension.extension",
"sliceName": "definition",
"min": 1,
"max": "1",
"mustSupport": true
},
{
"id": "Extension.extension:definition.extension",
"path": "Extension.extension.extension",
"max": "0"
},
{
"id": "Extension.extension:definition.url",
"path": "Extension.extension.url",
"fixedUri": "definition"
},
{
"id": "Extension.extension:definition.value[x]",
"path": "Extension.extension.value[x]",
"min": 1,
"type": [
{
"code": "canonical",
"targetProfile": [
"http://hl7.org/fhir/uv/application-feature/StructureDefinition/FeatureDefinition|1.0.0"
]
}
]
},
{
"id": "Extension.extension:value",
"path": "Extension.extension",
"sliceName": "value",
"min": 1,
"max": "1",
"mustSupport": true
},
{
"id": "Extension.extension:value.extension",
"path": "Extension.extension.extension",
"max": "0"
},
{
"id": "Extension.extension:value.url",
"path": "Extension.extension.url",
"fixedUri": "value"
},
{
"id": "Extension.extension:value.value[x]",
"path": "Extension.extension.value[x]",
"min": 1
},
{
"id": "Extension.url",
"path": "Extension.url",
"fixedUri": "http://hl7.org/fhir/uv/application-feature/StructureDefinition/feature"
},
{
"id": "Extension.value[x]",
"path": "Extension.value[x]",
"max": "0"
}
]
}
}
FHIR