IfcRelDeclares

Natural language names
Deklariert einen Kontext - Relation
Rel Declares
Change log
ItemSPFXMLChangeDescription
IFC2x3 to IFC4
    IfcRelDeclaresADDED
Semantic definitions at the entity
Entity definition

The objectified relationship IfcRelDeclares handles the declaration of objects (subtypes of IfcObject) or properties (subtypes of IfcPropertyDefinition) to a project or project library (represented by IfcProject, or IfcProjectLibrary).

The relationship handles the assignment of other objects, like IfcActor, or IfcTypeObject to the project, or project libary. The attribute RelatedDefinitions provides the references to the first level objects, that are the elements within the context. All other objects that relate to the first level objects are also defined in the context.

NOTE  Every object (as subtype of IfcObject) has to be declared within the context of a single IfcProject, or of a IfcProjectLibrary assigned to a single IfcProject. This declaration is transitive. For example: the IfcWorkPlan as first level object is declared within the context of IfcProject via IfcRelDeclares, all related IfcWorkSchedule's are related to the context in a transitive way through IfcWorkPlan.
NOTE  The assignment excludes subtypes of IfcProduct's, these are assigned to the IfcProject using the spatial structure approach through IfcSpatialStructureElement(s), where the outer container element such as IfcSite or IfcBuilding has an IfcRelAggregates relationship with the IfcProject.

The RelatingContext is the project, or project library that comprises all elements. The unit assignments and the presentation contexts defined at IfcProject or IfcProjectLibrary apply to all these elements.

HISTORY  New entity in IFC4.
Attribute definitions
#AttributeTypeCardinalityDescription G
5RelatingContextIfcContext Reference to the IfcProject to which additional information is assigned.X
6RelatedDefinitionsIfcDefinitionSelectS[1:?] Set of object or property definitions that are assigned to a context and to which the unit and representation context definitions of that context apply.X
Formal Propositions
RuleDescription
NoSelfReferenceThe instance to with the relation points shall not be contained in the set of RelatedObjects.
Inherited definitions from supertypes
Entity inheritance IfcRelationship IfcRoot
Attribute inheritance
#AttributeTypeCardinalityDescriptionG
IfcRoot
1GlobalIdIfcGloballyUniqueId Assignment of a globally unique identifier within the entire software world. X
2OwnerHistoryIfcOwnerHistory? Assignment of the information about the current ownership of that object, including owning actor, application, local identification and information captured about the recent changes of the object,
NOTE  only the last modification in stored - either as addition, deletion or modification.
IFC4 CHANGE  The attribute has been changed to be OPTIONAL.
X
3NameIfcLabel? Optional name for use by the participating software systems or users. For some subtypes of IfcRoot the insertion of the Name attribute may be required. This would be enforced by a where rule. X
4DescriptionIfcText? Optional description, provided for exchanging informative comments.X
IfcRelationship
IfcRelDeclares
5RelatingContextIfcContext Reference to the IfcProject to which additional information is assigned.X
6RelatedDefinitionsIfcDefinitionSelectS[1:?] Set of object or property definitions that are assigned to a context and to which the unit and representation context definitions of that context apply.X
Definitions applying to General Usage

Concept inheritance

#ConceptTemplateModel View
IfcRoot
IdentitySoftware IdentityGeneral Usage
Revision ControlRevision ControlGeneral Usage
Examples
Formal representations
XML Specification
 <xs:element name="IfcRelDeclares" type="ifc:IfcRelDeclares" substitutionGroup="ifc:IfcRelationship" nillable="true"/>
 <xs:complexType name="IfcRelDeclares">
  <xs:complexContent>
   <xs:extension base="ifc:IfcRelationship">
    <xs:sequence>
     <xs:element name="RelatedDefinitions">
      <xs:complexType>
       <xs:group ref="ifc:IfcDefinitionSelect" maxOccurs="unbounded"/>
       <xs:attribute ref="ifc:itemType" fixed="ifc:IfcDefinitionSelect"/>
       <xs:attribute ref="ifc:cType" fixed="set"/>
       <xs:attribute ref="ifc:arraySize" use="optional"/>
      </xs:complexType>
     </xs:element>
    </xs:sequence>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>
EXPRESS Specification
ENTITY IfcRelDeclares
 SUBTYPE OF (IfcRelationship);
  RelatingContext : IfcContext;
  RelatedDefinitions : SET [1:?] OF IfcDefinitionSelect;
 WHERE
  NoSelfReference : SIZEOF(QUERY(Temp <* RelatedDefinitions | RelatingContext :=: Temp)) = 0;
END_ENTITY;

Link to EXPRESS-G diagram EXPRESS-G diagram

References  References: IfcContext IfcObjectDefinition IfcPropertyDefinition

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