5.1.3.34 IfcRelDeclares
5.1.3.34.1 Semantic 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 library. The attribute RelatedDefinitions provides the references to the first level objects, that are the objects within the context. All other objects that relate to the first level objects are also defined in the context.
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. This assignment using IfcRelDeclares excludes every object (as subtype of IfcObject) already related to IfcProject via other relationships. For example, IfcSpatialStructureElement(s) that are related to IfcProject through IfcRelAggregates relationships; and subtypes of IfcProduct's that are contained in these IfcSpatialStructureElement(s) through IfcRelContainedInSpatialStructure relationships.The RelatingContext is the project, or project library that comprises all objects. The unit assignments and the presentation contexts defined at IfcProject or IfcProjectLibrary apply to all these objects.
New entity in IFC4.5.1.3.34.2 Entity inheritance
5.1.3.34.3 Attributes
| # | Attribute | Type | Description |
|---|---|---|---|
| IfcRoot (4) | |||
| 1 | GlobalId | IfcGloballyUniqueId |
Assignment of a globally unique identifier within the entire software world. |
| 2 | OwnerHistory | OPTIONAL IfcOwnerHistory |
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, Only the last modification is stored - either as addition, deletion or modification. The attribute has been changed to be OPTIONAL. |
| 3 | Name | OPTIONAL IfcLabel |
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. |
| 4 | Description | OPTIONAL IfcText |
Optional description, provided for exchanging informative comments. |
| Click to show 4 hidden inherited attributes Click to hide 4 inherited attributes | |||
| IfcRelDeclares (2) | |||
| 5 | RelatingContext | IfcContext |
Reference to the IfcProject to which additional information is assigned. |
| 6 | RelatedDefinitions | SET [1:?] OF IfcDefinitionSelect |
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. |
5.1.3.34.4 Formal propositions
| Name | Description |
|---|---|
| NoSelfReference |
The instance to which the relation points shall not be contained in the set of RelatedObjects. |
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5.1.3.34.5 Concept usage
| Concept | Usage | Description | |
|---|---|---|---|
| IfcRoot (2) | |||
| Revision Control | General |
Ownership, history, and merge state is captured using IfcOwnerHistory. |
|
| Software Identity | General |
IfcRoot assigns the globally unique ID. In addition it may provide for a name and a description about the concept. |
|
| Click to show 2 hidden inherited concepts Click to hide 2 inherited concepts | |||
5.1.3.34.6 Formal representation
ENTITY IfcRelDeclares
SUBTYPE OF (IfcRelationship);
RelatingContext : IfcContext;
RelatedDefinitions : SET [1:?] OF IfcDefinitionSelect;
WHERE
NoSelfReference : SIZEOF(QUERY(Temp <* RelatedDefinitions | RelatingContext :=: Temp)) = 0;
END_ENTITY;