8.6.3.5 IfcDocumentReference

RV ⓘ

AbV ⓘ

8.6.3.5.1 Semantic definition

An IfcDocumentReference is a reference to the location of a document. The reference is given by a system interpretable Location attribute (a URL string) where the document can be found, and an optional inherited internal reference Identification, which refers to a system interpretable position within the document. The optional inherited Name attribute is meant to have meaning for human readers. Optional document metadata can also be captured through reference to IfcDocumentInformation.

8.6.3.5.2 Entity inheritance

- IfcExternalReference

8.6.3.5.3 Attributes

#	Attribute	Type	Description
IfcExternalReference (4)
1	Location	OPTIONAL IfcURIReference	Location, where the external source (classification, document or library) can be accessed by electronic means. The electronic location is provided as an URI, and would normally be given as an URL location string. IFC4-CHANGE The data type has been changed from IfcLabel to IfcURIReference .
2	Identification	OPTIONAL IfcIdentifier	The Identification provides a unique identifier of the referenced item within the external source (classification, document or library). It may be provided as * a key, e.g. a classification notation, like NF2.3 * a handle * a uuid or guid It may be human readable (such as a key) or not (such as a handle or uuid) depending on the context of its usage (which has to be determined by local agreement). IFC4-CHANGE Attribute renamed from ItemReference for consistency.
3	Name	OPTIONAL IfcLabel	Optional name to further specify the reference. It can provide a human readable identifier (which does not necessarily need to have a counterpart in the internal structure of the document).
	ExternalReferenceForResources	SET [0:?] OF IfcExternalReferenceRelationship FOR RelatingReference	Reference to all associations between this external reference and objects within the IfcResourceObjectSelect that are tagged by the external reference. IFC4-CHANGE New inverse attribute added with upward compatibility.
Click to show 4 hidden inherited attributes
IfcDocumentReference (3)
4	Description	OPTIONAL IfcText	Description of the document reference for informational purposes. IFC4-CHANGE New attribute added at the end of the attribute list.
5	ReferencedDocument	OPTIONAL IfcDocumentInformation	The document that is referenced.
	DocumentRefForObjects	SET [0:?] OF IfcRelAssociatesDocument FOR RelatingDocument	The document reference with which objects are associated. IFC4-CHANGE New inverse attribute.

Table 8.6.3.5.C

8.6.3.5.4 Formal propositions

Name	Description
WR1	A name should only be given, if no document information (including the document name) is attached
`EXISTS(Name) XOR EXISTS(ReferencedDocument)`

Table 8.6.3.5.D

8.6.3.5.5 Examples

Figure 8.6.3.5.A

Reinforcing Stirrup
Figure 8.6.3.5.B

Reinforcing Assembly

8.6.3.5.6 Formal representation

 ENTITY IfcDocumentReference
 SUBTYPE OF (IfcExternalReference);
	Description : OPTIONAL IfcText;
	ReferencedDocument : OPTIONAL IfcDocumentInformation;
 INVERSE
	DocumentRefForObjects : SET [0:?] OF IfcRelAssociatesDocument FOR RelatingDocument;
 WHERE
	WR1 : EXISTS(Name) XOR EXISTS(ReferencedDocument);
END_ENTITY;