Re: includehosts mandatory?

Smith, Kevin, (R&D) VF-Group wrote:
> Hi Phil,
> 
> My understanding was that if we support other identifiers (ISAN, ISBN)
> etc. then <includehost>s would not be relevant for those, only for those
> retrievable over the Web.

True - but POWDER-BASE only has <in/excluderegex> with no other child 
elements allowed for <iriset>. Things like ISAN numbers would exist in a 
a format that is not POWDER but that can be transformed into 
POWDER-BASE. Therefore the question about <includehosts> only applies 
specifically to POWDER and not BASE or S.

> 
> NB a thought to park for now: so you could describe the characteristics
> of a bunch of SMTP addresses using POWDER, couldn't you? That seems
> quite powerful.

Yes indeed, and POWDER-BASE can do that, therefore conformant POWDER 
Processors can do that which is, I think, at the heart of the Stasinos 
plan.

> 
>>> It gives us a way to ensure syntactically that an IRI set is never
> empty
> It seems like we will need two-step validation due to some features
> absent in XML Schema, so this could be picked up by an additional check
> (we've mentioned using XSLT as a way to enforce business rules, and also
> to create a neat HTML page teling you what the DR says in plain
> English).

You're saying that we already need a 2-step validation and that we can 
therefore check that an IRI set definition is not empty without having 
to mandate <includehosts>? That would be good I think.

P