Extensibility-definitions

Release 5

This page is part of the FHIR Specification (v5.0.0: R5 - STU). This is the current published version. For a full list of available versions, see the Directory of published versions . Page versions: R5 R4B R4 R3 R2

2.1.5.3 Extension - Detailed Descriptions

FHIR Infrastructure icon Work Group Maturity Level: Normative Standards Status: Normative

Extension

Standards Status This element has a standards status of "Normative"

Definition

Optional Extension Element - found in all resources.

Short Display Optional Extensions Element

Cardinality 0..*

Type DataType

Requirements

The ability to add extensions in a structured way is what keeps FHIR resources simple.

Invariants

Defined on this element

ext-1 Rule Must have either extensions or value[x], not both extension.exists() != value.exists()

Extension.url

Definition

Source of the definition for the extension code - a logical name or a URL.

Short Display identifies the meaning of the extension

Cardinality 1..1

Type uri

Comments

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.

Extension.value[x]

Definition

Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

Short Display Value of extension

Cardinality 0..1

Type *

[x] Note See Choice of Datatypes for further information about how to use [x]

Invariants

Affect this element

ext-1 Rule Must have either extensions or value[x], not both extension.exists() != value.exists()