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Provide a way to specify unique identifiers
Provide an attribute to attach a unique identifier to any localizable item. This identifier should be unique within a document set, but should be identical across all translations of the same item.
being able to use such unique identifier allows
- a more effective re-use of translated text where content is re-used (either across update versions or across deliverables),
- possible re-usability across document using references
A possible attribute to use is the predefined xml:id attribute XML ID.
Note that, while an xml:id value is unique within a document and not necessarily within a set of documents, combining the xml:id value with the URI of the document would ensure a globally unique identifier.