There is also a case to be made for encoding the isbn as a URI (resource) instead of as a property or datatype. It turns out that MARC attaches properties to ISBNs, such as the fact that it's a large-print edition or a Braille edition.

Sometimes treating ISBNs as things like this is handy. Sure it's problematic sometimes too, but clues shouldn't always be ignored. :-/

On Jun 25, 2016, at 8:38 PM, Young,Jeff (OR) <[log in to unmask]<mailto:[log in to unmask]>> wrote:

One advantage of the property approach is that ex:isbn can be declared as:

ex:isbn rdfs:subPropertyOf ex:identifier .

For example:

ex:isbn rdfs:subPropertyOf dct:identifier .

I'm not aware of any commonly-used "identifier" datatypes that could serve as a basis for creating for sub-data types, but I might be wrong. Sub-property declarations are relatively common, and supported by existing tools.

Exotic datatypes seem like a backwater solution.


On Jun 25, 2016, at 8:10 PM, Tom Johnson <[log in to unmask]<mailto:[log in to unmask]>> wrote:

Hi Jeff,

> It would only require defining ex:isbn as a property, which seem more in keeping with the spirit of RDF.

I'm not clear on the way this would be more in keeping with RDF. Under the RDF (recognizing D) semantics, it seems like the datatype has clear benefits. Is there a reason to discount those.

- Tom