type-specifier
type: StructureDefinition
node role: treeRoot
id:
  v: type-specifier
language:
  v: es
text:
  status:
    v: extensions
  div:
    v: Spanish Generated Narrative: StructureDefinition type-specifier Language: en Name Flags Card. Type Description & Constraints<img src="[binary]" alt="doco" style="background-color: inherit"/> Extension 0..* Extension Indicates that this repeating element is represented as an object in json and the named one of the two sub-elements is the key for the other one #xD; Slices for extension 2..2 Extension Extension Slice: Unordered, Closed by value:url #xD; Slices for extension Content/Rules for all slices #xD; extension:condition 1..1 Extension Condition for this type (FHIRPath) #xD; extension 0..0 Extension #xD; url 1..1 uri "condition" #xD; value[x] 1..1 string Value of extension #xD; Slices for extension Content/Rules for all slices #xD; extension:type 1..1 Extension The type (uri - usually full URI of logical model type_ #xD; extension 0..0 Extension #xD; url 1..1 uri "type" #xD; value[x] 1..1 code Value of extension #xD; url 1..1 uri "http://hl7.org/fhir/tools/StructureDefinition/type-specifier" #xD; value[x] 0..0 Value of extension #xD; <img src="[binary]" alt="doco" style="background-color: inherit"/> Documentation for this format
extension:
  url:
    v: http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm
    l: structuredefinition-fmm
  value: Integer
    v: 3
extension:
  url:
    v: http://hl7.org/fhir/StructureDefinition/structuredefinition-wg
    l: structuredefinition-wg
  value: Code
    v: fhir
extension:
  url:
    v: http://hl7.org/fhir/StructureDefinition/structuredefinition-type-characteristics
    l: structuredefinition-type-characteristics
  value: Code
    v: can-bind
extension:
  url:
    v: http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status
    l: structuredefinition-standards-status
  value: Code
    v: informative
    extension:
      url:
        v: http://hl7.org/fhir/StructureDefinition/structuredefinition-conformance-derivedFrom
        l: structuredefinition-conformance-derivedFrom
      value: Canonical
        v: http://hl7.org/fhir/tools/ImplementationGuide/hl7.fhir.uv.tools
        l: hl7.fhir.uv.tools
url:
  v: http://hl7.org/fhir/tools/StructureDefinition/type-specifier
  l: type-specifier
identifier:
  system:
    v: urn:ietf:rfc:3986
    l: 3986
  value:
    v: urn:oid:2.16.840.1.113883.4.642.40.1.42.41
version:
  v: 1.1.2
name:
  v: TypeSpecifier
title:
  v: Type Specifier Extension
status:
  v: active
experimental:
  v: false
date:
  v: 2026-03-24T18:51:49+00:00
publisher:
  v: HL7 International / FHIR Infrastructure
contact:
  telecom:
    system:
      v: url
    value:
      v: http://www.hl7.org/Special/committees/fiwg
description:
  v: In some logical models, the type of content at one location depends on the value of some other element, and the type is otherwise not explicit in the instance. In such cases, the type of the element is assigned an abstract ancestor type, and this extension specifies how to determine what type is actually used
jurisdiction:
  coding:
    system:
      v: http://unstats.un.org/unsd/methods/m49/m49.htm
      l: m49.htm
    code:
      v: 001
fhir version:
  v: 5.0.0
mapping:
  identity:
    v: rim
  uri:
    v: http://hl7.org/v3
    l: v3
  name:
    v: RIM Mapping
kind:
  v: complex-type
abstract:
  v: false
context:
  type:
    v: element
  expression:
    v: ElementDefinition
type:
  v: Extension
  l: Extension
base definition:
  v: http://hl7.org/fhir/StructureDefinition/Extension
  l: Extension
derivation:
  v: constraint
snapshot:
  extension:
    url:
      v: http://hl7.org/fhir/tools/StructureDefinition/snapshot-base-version
      l: snapshot-base-version
    value: String
      v: 5.0.0
  element:
    id:
      v: Extension
    path:
      v: Extension
    short:
      v: Indicates that this repeating element is represented as an object in json and the named one of the two sub-elements is the key for the other one
    definition:
      v: type-specifiers applied to bindable elements.
    min:
      v: 0
    max:
      v: *
    base:
      path:
        v: Extension
      min:
        v: 0
      max:
        v: *
    constraint:
      key:
        v: ele-1
      severity:
        v: error
      human:
        v: All FHIR elements must have a @value or children
      expression:
        v: hasValue() or (children().count() > id.count())
      source:
        v: http://hl7.org/fhir/StructureDefinition/Element
        l: Element
    constraint:
      key:
        v: ext-1
      severity:
        v: error
      human:
        v: Must have either extensions or value[x], not both
      expression:
        v: extension.exists() != value.exists()
      source:
        v: http://hl7.org/fhir/StructureDefinition/Extension
        l: Extension
    is modifier:
      v: false
  element:
    id:
      v: Extension.id
    path:
      v: Extension.id
    representation:
      v: xmlAttr
    short:
      v: Unique id for inter-element referencing
    definition:
      v: Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
    min:
      v: 0
    max:
      v: 1
    base:
      path:
        v: Element.id
      min:
        v: 0
      max:
        v: 1
    type:
      extension:
        value: Url
      code:
        v: http://hl7.org/fhirpath/System.String
        l: System.String
    condition:
      v: ele-1
    is modifier:
      v: false
    is summary:
      v: false
    mapping:
      identity:
        v: rim
      map:
        v: n/a
  element:
    id:
      v: Extension.extension

Url
v: id
l: id

v: Extension.extension

discriminator:
  type:
    v: value
  path:
    v: url
description:
  v: Extensions are always sliced by (at least) url
rules:
  v: closed

v: Extension

v: An Extension

v: 2

v: 2

path:
  v: Element.extension
min:
  v: 0
max:
  v: *

code:
  v: Extension
  l: Extension

key:
  v: ele-1
severity:
  v: error
human:
  v: All FHIR elements must have a @value or children
expression:
  v: hasValue() or (children().count() > id.count())
source:
  v: http://hl7.org/fhir/StructureDefinition/Element
  l: Element

key:
  v: ext-1
severity:
  v: error
human:
  v: Must have either extensions or value[x], not both
expression:
  v: extension.exists() != value.exists()
source:
  v: http://hl7.org/fhir/StructureDefinition/Extension
  l: Extension

v: false

v: false

id:
  v: Extension.extension:condition
path:
  v: Extension.extension
slice name:
  v: condition
short:
  v: Condition for this type (FHIRPath)
definition:
  v: The FHIRPath expression for this type to be true.
min:
  v: 1
max:
  v: 1
base:
  path:
    v: Element.extension
  min:
    v: 0
  max:
    v: *
type:
  code:
    v: Extension
    l: Extension
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
constraint:
  key:
    v: ext-1
  severity:
    v: error
  human:
    v: Must have either extensions or value[x], not both
  expression:
    v: extension.exists() != value.exists()
  source:
    v: http://hl7.org/fhir/StructureDefinition/Extension
    l: Extension
is modifier:
  v: false
is summary:
  v: false

id:
  v: Extension.extension:condition.id
path:
  v: Extension.extension.id
representation:
  v: xmlAttr
short:
  v: Unique id for inter-element referencing
definition:
  v: Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
min:
  v: 0
max:
  v: 1
base:
  path:
    v: Element.id
  min:
    v: 0
  max:
    v: 1
type:
  extension:
    url:
      v: http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type
      l: structuredefinition-fhir-type
    value: Url
      v: id
      l: id
  code:
    v: http://hl7.org/fhirpath/System.String
    l: System.String
condition:
  v: ele-1
is modifier:
  v: false
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: n/a

id:
  v: Extension.extension:condition.extension
path:
  v: Extension.extension.extension
slicing:
  discriminator:
    type:
      v: value
    path:
      v: url
  description:
    v: Extensions are always sliced by (at least) url
  rules:
    v: open
short:
  v: Extension
definition:
  v: An Extension
min:
  v: 0
max:
  v: 0
base:
  path:
    v: Element.extension
  min:
    v: 0
  max:
    v: *
type:
  code:
    v: Extension
    l: Extension
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
constraint:
  key:
    v: ext-1
  severity:
    v: error
  human:
    v: Must have either extensions or value[x], not both
  expression:
    v: extension.exists() != value.exists()
  source:
    v: http://hl7.org/fhir/StructureDefinition/Extension
    l: Extension
is modifier:
  v: false
is summary:
  v: false

id:
  v: Extension.extension:condition.url
path:
  v: Extension.extension.url
representation:
  v: xmlAttr
short:
  v: identifies the meaning of the extension
definition:
  v: Source of the definition for the extension code - a logical name or a URL.
comment:
  v: 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:
  v: 1
max:
  v: 1
base:
  path:
    v: Extension.url
  min:
    v: 1
  max:
    v: 1
type:
  code:
    v: uri
    l: uri
fixed: Uri
  v: condition
  l: condition
is modifier:
  v: false
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: N/A

id:
  v: Extension.extension:condition.value[x]
path:
  v: Extension.extension.value[x]
short:
  v: Value of extension
definition:
  v: 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:
  v: 1
max:
  v: 1
base:
  path:
    v: Extension.value[x]
  min:
    v: 0
  max:
    v: 1
type:
  code:
    v: string
    l: string
condition:
  v: ext-1
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
is modifier:
  v: false
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: N/A

id:
  v: Extension.extension:type
path:
  v: Extension.extension
slice name:
  v: type
short:
  v: The type (uri - usually full URI of logical model type_
definition:
  v: An Extension
min:
  v: 1
max:
  v: 1
base:
  path:
    v: Element.extension
  min:
    v: 0
  max:
    v: *
type:
  code:
    v: Extension
    l: Extension
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
constraint:
  key:
    v: ext-1
  severity:
    v: error
  human:
    v: Must have either extensions or value[x], not both
  expression:
    v: extension.exists() != value.exists()
  source:
    v: http://hl7.org/fhir/StructureDefinition/Extension
    l: Extension
is modifier:
  v: false
is summary:
  v: false

id:
  v: Extension.extension:type.id
path:
  v: Extension.extension.id
representation:
  v: xmlAttr
short:
  v: Unique id for inter-element referencing
definition:
  v: Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
min:
  v: 0
max:
  v: 1
base:
  path:
    v: Element.id
  min:
    v: 0
  max:
    v: 1
type:
  extension:
    url:
      v: http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type
      l: structuredefinition-fhir-type
    value: Url
      v: id
      l: id
  code:
    v: http://hl7.org/fhirpath/System.String
    l: System.String
condition:
  v: ele-1
is modifier:
  v: false
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: n/a

id:
  v: Extension.extension:type.extension
path:
  v: Extension.extension.extension
slicing:
  discriminator:
    type:
      v: value
    path:
      v: url
  description:
    v: Extensions are always sliced by (at least) url
  rules:
    v: open
short:
  v: Extension
definition:
  v: An Extension
min:
  v: 0
max:
  v: 0
base:
  path:
    v: Element.extension
  min:
    v: 0
  max:
    v: *
type:
  code:
    v: Extension
    l: Extension
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
constraint:
  key:
    v: ext-1
  severity:
    v: error
  human:
    v: Must have either extensions or value[x], not both
  expression:
    v: extension.exists() != value.exists()
  source:
    v: http://hl7.org/fhir/StructureDefinition/Extension
    l: Extension
is modifier:
  v: false
is summary:
  v: false

id:
  v: Extension.extension:type.url
path:
  v: Extension.extension.url
representation:
  v: xmlAttr
short:
  v: identifies the meaning of the extension
definition:
  v: Source of the definition for the extension code - a logical name or a URL.
comment:
  v: 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:
  v: 1
max:
  v: 1
base:
  path:
    v: Extension.url
  min:
    v: 1
  max:
    v: 1
type:
  code:
    v: uri
    l: uri
fixed: Uri
  v: type
  l: type
is modifier:
  v: false
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: N/A

id:
  v: Extension.extension:type.value[x]
path:
  v: Extension.extension.value[x]
short:
  v: Value of extension
definition:
  v: 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:
  v: 1
max:
  v: 1
base:
  path:
    v: Extension.value[x]
  min:
    v: 0
  max:
    v: 1
type:
  code:
    v: code
    l: code
condition:
  v: ext-1
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
is modifier:
  v: false
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: N/A

id:
  v: Extension.url
path:
  v: Extension.url
representation:
  v: xmlAttr
short:
  v: identifies the meaning of the extension
definition:
  v: Source of the definition for the extension code - a logical name or a URL.
comment:
  v: 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:
  v: 1
max:
  v: 1
base:
  path:
    v: Extension.url
  min:
    v: 1
  max:
    v: 1
type:
  extension:
    url:
      v: http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type
      l: structuredefinition-fhir-type
    value: Url
      v: uri
      l: uri
  code:
    v: http://hl7.org/fhirpath/System.String
    l: System.String
fixed: Uri
  v: http://hl7.org/fhir/tools/StructureDefinition/type-specifier
  l: type-specifier
is modifier:
  v: false
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: N/A

id:
  v: Extension.value[x]
path:
  v: Extension.value[x]
short:
  v: Value of extension
definition:
  v: 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:
  v: 0
max:
  v: 0
base:
  path:
    v: Extension.value[x]
  min:
    v: 0
  max:
    v: 1
type:
  code:
    v: base64Binary
    l: base64Binary
type:
  code:
    v: boolean
    l: boolean
type:
  code:
    v: canonical
    l: canonical
type:
  code:
    v: code
    l: code
type:
  code:
    v: date
    l: date
type:
  code:
    v: dateTime
    l: dateTime
type:
  code:
    v: decimal
    l: decimal
type:
  code:
    v: id
    l: id
type:
  code:
    v: instant
    l: instant
type:
  code:
    v: integer
    l: integer
type:
  code:
    v: integer64
    l: integer64
type:
  code:
    v: markdown
    l: markdown
type:
  code:
    v: oid
    l: oid
type:
  code:
    v: positiveInt
    l: positiveInt
type:
  code:
    v: string
    l: string
type:
  code:
    v: time
    l: time
type:
  code:
    v: unsignedInt
    l: unsignedInt
type:
  code:
    v: uri
    l: uri
type:
  code:
    v: url
    l: url
type:
  code:
    v: uuid
    l: uuid
type:
  code:
    v: Address
    l: Address
type:
  code:
    v: Age
    l: Age
type:
  code:
    v: Annotation
    l: Annotation
type:
  code:
    v: Attachment
    l: Attachment
type:
  code:
    v: CodeableConcept
    l: CodeableConcept
type:
  code:
    v: CodeableReference
    l: CodeableReference
type:
  code:
    v: Coding
    l: Coding
type:
  code:
    v: ContactPoint
    l: ContactPoint
type:
  code:
    v: Count
    l: Count
type:
  code:
    v: Distance
    l: Distance
type:
  code:
    v: Duration
    l: Duration
type:
  code:
    v: HumanName
    l: HumanName
type:
  code:
    v: Identifier
    l: Identifier
type:
  code:
    v: Money
    l: Money
type:
  code:
    v: Period
    l: Period
type:
  code:
    v: Quantity
    l: Quantity
type:
  code:
    v: Range
    l: Range
type:
  code:
    v: Ratio
    l: Ratio
type:
  code:
    v: RatioRange
    l: RatioRange
type:
  code:
    v: Reference
    l: Reference
type:
  code:
    v: SampledData
    l: SampledData
type:
  code:
    v: Signature
    l: Signature
type:
  code:
    v: Timing
    l: Timing
type:
  code:
    v: ContactDetail
    l: ContactDetail
type:
  code:
    v: DataRequirement
    l: DataRequirement
type:
  code:
    v: Expression
    l: Expression

code:
  v: ParameterDefinition
  l: ParameterDefinition

code:
  v: RelatedArtifact
  l: RelatedArtifact

code:
  v: TriggerDefinition
  l: TriggerDefinition

code:
  v: UsageContext
  l: UsageContext

code:
  v: Availability
  l: Availability

code:
  v: ExtendedContactDetail
  l: ExtendedContactDetail

code:
  v: Dosage
  l: Dosage

code:
  v: Meta
  l: Meta

v: ext-1

key:
  v: ele-1
severity:
  v: error
human:
  v: All FHIR elements must have a @value or children
expression:
  v: hasValue() or (children().count() > id.count())
source:
  v: http://hl7.org/fhir/StructureDefinition/Element
  l: Element

v: false

v: false

identity:
  v: rim
map:
  v: N/A

element:
  id:
    v: Extension
  path:
    v: Extension
  short:
    v: Indicates that this repeating element is represented as an object in json and the named one of the two sub-elements is the key for the other one
  definition:
    v: type-specifiers applied to bindable elements.
  min:
    v: 0
  max:
    v: *
element:
  id:
    v: Extension.extension
  path:
    v: Extension.extension
  slicing:
    discriminator:
      type:
        v: value
      path:
        v: url
    description:
      v: Extensions are sliced by url
    rules:
      v: closed
  min:
    v: 2
  max:
    v: 2
element:
  id:
    v: Extension.extension:condition
  path:
    v: Extension.extension
  slice name:
    v: condition
  short:
    v: Condition for this type (FHIRPath)
  definition:
    v: The FHIRPath expression for this type to be true.
  min:
    v: 1
  max:
    v: 1
  type:
    code:
      v: Extension
      l: Extension
element:
  id:
    v: Extension.extension:condition.extension
  path:
    v: Extension.extension.extension
  max:
    v: 0
element:
  id:
    v: Extension.extension:condition.url
  path:
    v: Extension.extension.url
  type:
    code:
      v: uri
      l: uri
  fixed: Uri
    v: condition
    l: condition
element:
  id:
    v: Extension.extension:condition.value[x]
  path:
    v: Extension.extension.value[x]
  min:
    v: 1
  type:
    code:
      v: string
      l: string
element:
  id:
    v: Extension.extension:type
  path:
    v: Extension.extension
  slice name:
    v: type
  short:
    v: The type (uri - usually full URI of logical model type_
  min:
    v: 1
  max:
    v: 1
  type:
    code:
      v: Extension
      l: Extension
element:
  id:
    v: Extension.extension:type.extension
  path:
    v: Extension.extension.extension
  max:
    v: 0
element:
  id:
    v: Extension.extension:type.url
  path:
    v: Extension.extension.url
  type:
    code:
      v: uri
      l: uri
  fixed: Uri
    v: type
    l: type
element:
  id:
    v: Extension.extension:type.value[x]
  path:
    v: Extension.extension.value[x]
  min:
    v: 1
  type:
    code:
      v: code
      l: code
element:
  id:
    v: Extension.url
  path:
    v: Extension.url
  fixed: Uri
    v: http://hl7.org/fhir/tools/StructureDefinition/type-specifier
    l: type-specifier
element:
  id:
    v: Extension.value[x]
  path:
    v: Extension.value[x]
  max:
    v: 0