This element assigns a category to the parent element. The category is intended to specialize the usage and/or the content identifiable object. Such a specialization may also impose particular semantic constraints on the entire substructure (not only the identifiable itself).<br/>
The purpose of this attribute is to provide a globally unique identifier for an instance of a metaclass. The values of this attribute should be globally unique strings prefixed by the type of identifier. For example, to include a<br/>DCE UUID as defined by The Open Group, the UUID would be preceded by "DCE:". The values of this attribute may be used to support merging of different models. <br/>The form of the UUID (Universally Unique Identifier) is taken from a standard defined by the Open Group (was Open Software Foundation). This standard is widely used, including by Microsoft for COM (GUIDs) and by many companies for DCE, which is based on CORBA. The method for generating these 128-bit IDs is published in the standard and the effectiveness and uniqueness of the IDs is not in practice disputed.<br/>If the id namespace is omitted, DCE is assumed. <br/>An example is "DCE:2fac1234-31f8-11b4-a222-08002b34c003".<br/>
Name: optionalElement
This association points to the actual element in the core model that is marked optional by this VariableElement. The VariableElement in the variability extension can thus be seen as merely a marker element (this marker mechanism follows the global guideline for relating EAST-ADL extensions to the core and is not specific to the variability extension).
Name: privateElement
This association points to the actual element in the core model that is marked private by this PrivateContent object. Instances of the PrivateContent meta-class in the variability extension can thus be seen as merely a marker object (this marker mechanism follows the global guideline for relating the EAST-ADL extensions to the core and is not specific to the variability extension).
Name: configurableElement
This association points to the actual element in the core model that is marked as a configurable container of some variable content by this ConfigurableContainer. The ConfigurableContainer in the variability extension can thus be seen as merely a marker element (this marker mechanism follows the global guideline for relating the EAST-ADL extensions to the core and is not specific to the variability extension).