R4 Ballot #1 (Mixed Normative/Trial use)

This page is part of the FHIR Specification (v3.3.0: R4 Ballot 2). The current version which supercedes this version is 5.0.0. For a full list of available versions, see the Directory of published versions . Page versions: R4B R4 R3

Extension-codesystem-history.json

Vocabulary Work GroupMaturity Level: N/ABallot Status: Informative

Raw JSON (canonical form)

history

{
  "resourceType": "StructureDefinition",
  "id": "codesystem-history",
  "extension": [
    {
      "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-wg",
      "valueCode": "vocab"
    },
    {
      "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm",
      "valueInteger": 1
    }
  ],
  "url": "http://hl7.org/fhir/StructureDefinition/codesystem-history",
  "name": "history",
  "status": "draft",
  "date": "2018-04-03T12:05:46+10:00",
  "publisher": "HL7",
  "description": "Information on changes made to the Value Set Definition over time, and also has a contained audit trail of all such changes.",
  "fhirVersion": "3.3.0",
  "mapping": [
    {
      "identity": "rim",
      "uri": "http://hl7.org/v3",
      "name": "RIM Mapping"
    }
  ],
  "kind": "complex-type",
  "abstract": false,
  "context": [
    {
      "type": "element",
      "expression": "CodeSystem"
    }
  ],
  "type": "Extension",
  "baseDefinition": "http://hl7.org/fhir/StructureDefinition/Extension",
  "derivation": "constraint",
  "snapshot": {
    "element": [
      {
        "id": "Extension",
        "path": "Extension",
        "short": "What has happened over time",
        "definition": "Information on changes made to the Value Set Definition over time, and also has a contained audit trail of all such changes.",
        "min": 0,
        "max": "*",
        "base": {
          "path": "Extension",
          "min": 0,
          "max": "*"
        },
        "condition": [
          "ele-1"
        ],
        "constraint": [
          {
            "key": "ele-1",
            "severity": "error",
            "human": "All FHIR elements must have a @value or children",
            "expression": "hasValue() | (children().count() > id.count())",
            "xpath": "@value|f:*|h:div",
            "source": "Element"
          },
          {
            "key": "ext-1",
            "severity": "error",
            "human": "Must have either extensions or value[x], not both",
            "expression": "extension.exists() != value.exists()",
            "xpath": "exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])",
            "source": "Extension"
          }
        ],
        "isModifier": false
      },
      {
        "id": "Extension.id",
        "path": "Extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "xml:id (or equivalent in JSON)",
        "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": [
          {
            "code": "string"
          }
        ],
        "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": "Additional content defined by implementations",
        "definition": "May be used to represent additional information that is not part of the basic definition of the element. 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.",
        "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.",
        "alias": [
          "extensions",
          "user content"
        ],
        "min": 0,
        "max": "*",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]
      },
      {
        "id": "Extension.extension:name",
        "path": "Extension.extension",
        "sliceName": "name",
        "short": "The name of this set of history entries",
        "definition": "Label for a set of entries, such as a version.",
        "comment": "Typically, a value set will have a set of history entries for each major publication milestone.",
        "min": 0,
        "max": "1",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false,
        "isSummary": false
      },
      {
        "id": "Extension.extension:name.id",
        "path": "Extension.extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "xml:id (or equivalent in JSON)",
        "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": [
          {
            "code": "string"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]
      },
      {
        "id": "Extension.extension:name.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"
          }
        ],
        "isModifier": false,
        "isSummary": false
      },
      {
        "id": "Extension.extension:name.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": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "name",
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:name.valueString",
        "path": "Extension.extension.valueString",
        "short": "Value of extension",
        "definition": "Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list).",
        "min": 0,
        "max": "1",
        "base": {
          "path": "Extension.value[x]",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "code": "string"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:revision",
        "path": "Extension.extension",
        "sliceName": "revision",
        "short": "Audit of all changes for a history entry",
        "definition": "A list of specific changes, who made them and when.",
        "min": 0,
        "max": "*",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false,
        "isSummary": false
      },
      {
        "id": "Extension.extension:revision.id",
        "path": "Extension.extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "xml:id (or equivalent in JSON)",
        "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": [
          {
            "code": "string"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.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"
          }
        ],
        "isModifier": false,
        "isSummary": false
      },
      {
        "id": "Extension.extension:revision.extension:date",
        "path": "Extension.extension.extension",
        "sliceName": "date",
        "short": "Date the change was made",
        "definition": "Date the change took place.",
        "min": 1,
        "max": "1",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false,
        "isSummary": false
      },
      {
        "id": "Extension.extension:revision.extension:date.id",
        "path": "Extension.extension.extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "xml:id (or equivalent in JSON)",
        "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": [
          {
            "code": "string"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:date.extension",
        "path": "Extension.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"
          }
        ],
        "isModifier": false,
        "isSummary": false
      },
      {
        "id": "Extension.extension:revision.extension:date.url",
        "path": "Extension.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": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "date",
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:date.valueDateTime",
        "path": "Extension.extension.extension.valueDateTime",
        "short": "Value of extension",
        "definition": "Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list).",
        "min": 0,
        "max": "1",
        "base": {
          "path": "Extension.value[x]",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "code": "dateTime"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:id",
        "path": "Extension.extension.extension",
        "sliceName": "id",
        "short": "Version marker after the change was made",
        "definition": "Unique id for the specific change.",
        "min": 1,
        "max": "1",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false,
        "isSummary": false
      },
      {
        "id": "Extension.extension:revision.extension:id.id",
        "path": "Extension.extension.extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "xml:id (or equivalent in JSON)",
        "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": [
          {
            "code": "string"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:id.extension",
        "path": "Extension.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"
          }
        ],
        "isModifier": false,
        "isSummary": false
      },
      {
        "id": "Extension.extension:revision.extension:id.url",
        "path": "Extension.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": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "id",
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:id.valueString",
        "path": "Extension.extension.extension.valueString",
        "short": "Value of extension",
        "definition": "Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list).",
        "min": 0,
        "max": "1",
        "base": {
          "path": "Extension.value[x]",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "code": "string"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:author",
        "path": "Extension.extension.extension",
        "sliceName": "author",
        "short": "Who made the change",
        "definition": "Person or device responsible for the change.",
        "min": 1,
        "max": "1",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false,
        "isSummary": false
      },
      {
        "id": "Extension.extension:revision.extension:author.id",
        "path": "Extension.extension.extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "xml:id (or equivalent in JSON)",
        "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": [
          {
            "code": "string"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:author.extension",
        "path": "Extension.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"
          }
        ],
        "isModifier": false,
        "isSummary": false
      },
      {
        "id": "Extension.extension:revision.extension:author.url",
        "path": "Extension.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": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "author",
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:author.valueString",
        "path": "Extension.extension.extension.valueString",
        "short": "Value of extension",
        "definition": "Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list).",
        "min": 0,
        "max": "1",
        "base": {
          "path": "Extension.value[x]",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "code": "string"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:notes",
        "path": "Extension.extension.extension",
        "sliceName": "notes",
        "short": "Information about the change",
        "definition": "Description of exactly what was changed and how.",
        "min": 0,
        "max": "1",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false,
        "isSummary": false
      },
      {
        "id": "Extension.extension:revision.extension:notes.id",
        "path": "Extension.extension.extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "xml:id (or equivalent in JSON)",
        "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": [
          {
            "code": "string"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:notes.extension",
        "path": "Extension.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"
          }
        ],
        "isModifier": false,
        "isSummary": false
      },
      {
        "id": "Extension.extension:revision.extension:notes.url",
        "path": "Extension.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": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "notes",
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:notes.valueString",
        "path": "Extension.extension.extension.valueString",
        "short": "Value of extension",
        "definition": "Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list).",
        "min": 0,
        "max": "1",
        "base": {
          "path": "Extension.value[x]",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "code": "string"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.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": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "revision",
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.value[x]",
        "path": "Extension.extension.value[x]",
        "short": "Value of extension",
        "definition": "Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for 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": "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": "Coding"
          },
          {
            "code": "ContactPoint"
          },
          {
            "code": "Count"
          },
          {
            "code": "Distance"
          },
          {
            "code": "Duration"
          },
          {
            "code": "HumanName"
          },
          {
            "code": "Identifier"
          },
          {
            "code": "Money"
          },
          {
            "code": "Period"
          },
          {
            "code": "Quantity"
          },
          {
            "code": "Range"
          },
          {
            "code": "Ratio"
          },
          {
            "code": "Reference"
          },
          {
            "code": "SampledData"
          },
          {
            "code": "Signature"
          },
          {
            "code": "Timing"
          },
          {
            "code": "ParameterDefinition"
          },
          {
            "code": "DataRequirement"
          },
          {
            "code": "RelatedArtifact"
          },
          {
            "code": "ContactDetail"
          },
          {
            "code": "Contributor"
          },
          {
            "code": "TriggerDefinition"
          },
          {
            "code": "UsageContext"
          },
          {
            "code": "Dosage"
          }
        ],
        "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": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "http://hl7.org/fhir/StructureDefinition/codesystem-history",
        "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 - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for 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": "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": "Coding"
          },
          {
            "code": "ContactPoint"
          },
          {
            "code": "Count"
          },
          {
            "code": "Distance"
          },
          {
            "code": "Duration"
          },
          {
            "code": "HumanName"
          },
          {
            "code": "Identifier"
          },
          {
            "code": "Money"
          },
          {
            "code": "Period"
          },
          {
            "code": "Quantity"
          },
          {
            "code": "Range"
          },
          {
            "code": "Ratio"
          },
          {
            "code": "Reference"
          },
          {
            "code": "SampledData"
          },
          {
            "code": "Signature"
          },
          {
            "code": "Timing"
          },
          {
            "code": "ParameterDefinition"
          },
          {
            "code": "DataRequirement"
          },
          {
            "code": "RelatedArtifact"
          },
          {
            "code": "ContactDetail"
          },
          {
            "code": "Contributor"
          },
          {
            "code": "TriggerDefinition"
          },
          {
            "code": "UsageContext"
          },
          {
            "code": "Dosage"
          }
        ],
        "isModifier": false,
        "isSummary": false,
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      }
    ]
  },
  "differential": {
    "element": [
      {
        "id": "Extension",
        "path": "Extension",
        "short": "What has happened over time",
        "definition": "Information on changes made to the Value Set Definition over time, and also has a contained audit trail of all such changes.",
        "min": 0,
        "max": "*",
        "isModifier": false
      },
      {
        "id": "Extension.extension:name",
        "path": "Extension.extension",
        "sliceName": "name",
        "short": "The name of this set of history entries",
        "definition": "Label for a set of entries, such as a version.",
        "comment": "Typically, a value set will have a set of history entries for each major publication milestone.",
        "min": 0,
        "max": "1",
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false
      },
      {
        "id": "Extension.extension:name.extension",
        "path": "Extension.extension.extension",
        "max": "0"
      },
      {
        "id": "Extension.extension:name.url",
        "path": "Extension.extension.url",
        "type": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "name"
      },
      {
        "id": "Extension.extension:name.valueString",
        "path": "Extension.extension.valueString",
        "type": [
          {
            "code": "string"
          }
        ]
      },
      {
        "id": "Extension.extension:revision",
        "path": "Extension.extension",
        "sliceName": "revision",
        "short": "Audit of all changes for a history entry",
        "definition": "A list of specific changes, who made them and when.",
        "min": 0,
        "max": "*",
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false
      },
      {
        "id": "Extension.extension:revision.extension",
        "path": "Extension.extension.extension",
        "max": "0"
      },
      {
        "id": "Extension.extension:revision.extension:date",
        "path": "Extension.extension.extension",
        "sliceName": "date",
        "short": "Date the change was made",
        "definition": "Date the change took place.",
        "min": 1,
        "max": "1",
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false
      },
      {
        "id": "Extension.extension:revision.extension:date.extension",
        "path": "Extension.extension.extension.extension",
        "max": "0"
      },
      {
        "id": "Extension.extension:revision.extension:date.url",
        "path": "Extension.extension.extension.url",
        "type": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "date"
      },
      {
        "id": "Extension.extension:revision.extension:date.valueDateTime",
        "path": "Extension.extension.extension.valueDateTime",
        "type": [
          {
            "code": "dateTime"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:id",
        "path": "Extension.extension.extension",
        "sliceName": "id",
        "short": "Version marker after the change was made",
        "definition": "Unique id for the specific change.",
        "min": 1,
        "max": "1",
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false
      },
      {
        "id": "Extension.extension:revision.extension:id.extension",
        "path": "Extension.extension.extension.extension",
        "max": "0"
      },
      {
        "id": "Extension.extension:revision.extension:id.url",
        "path": "Extension.extension.extension.url",
        "type": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "id"
      },
      {
        "id": "Extension.extension:revision.extension:id.valueString",
        "path": "Extension.extension.extension.valueString",
        "type": [
          {
            "code": "string"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:author",
        "path": "Extension.extension.extension",
        "sliceName": "author",
        "short": "Who made the change",
        "definition": "Person or device responsible for the change.",
        "min": 1,
        "max": "1",
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false
      },
      {
        "id": "Extension.extension:revision.extension:author.extension",
        "path": "Extension.extension.extension.extension",
        "max": "0"
      },
      {
        "id": "Extension.extension:revision.extension:author.url",
        "path": "Extension.extension.extension.url",
        "type": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "author"
      },
      {
        "id": "Extension.extension:revision.extension:author.valueString",
        "path": "Extension.extension.extension.valueString",
        "type": [
          {
            "code": "string"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.extension:notes",
        "path": "Extension.extension.extension",
        "sliceName": "notes",
        "short": "Information about the change",
        "definition": "Description of exactly what was changed and how.",
        "min": 0,
        "max": "1",
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false
      },
      {
        "id": "Extension.extension:revision.extension:notes.extension",
        "path": "Extension.extension.extension.extension",
        "max": "0"
      },
      {
        "id": "Extension.extension:revision.extension:notes.url",
        "path": "Extension.extension.extension.url",
        "type": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "notes"
      },
      {
        "id": "Extension.extension:revision.extension:notes.valueString",
        "path": "Extension.extension.extension.valueString",
        "type": [
          {
            "code": "string"
          }
        ]
      },
      {
        "id": "Extension.extension:revision.url",
        "path": "Extension.extension.url",
        "type": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "revision"
      },
      {
        "id": "Extension.extension:revision.value[x]",
        "path": "Extension.extension.value[x]",
        "min": 0,
        "max": "0"
      },
      {
        "id": "Extension.url",
        "path": "Extension.url",
        "type": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "http://hl7.org/fhir/StructureDefinition/codesystem-history"
      },
      {
        "id": "Extension.value[x]",
        "path": "Extension.value[x]",
        "min": 0,
        "max": "0"
      }
    ]
  }
}

Usage note: every effort has been made to ensure that the examples are correct and useful, but they are not a normative part of the specification.