Re: Some thoughts on the RDFa DOM API document

On Apr 27, 2010, at 08:38 , Shane McCarron wrote:

> 
> 
> Benjamin Adrian wrote:
[snip]
>> 
>> 
>> 2. I assume that the designation of BlankNodes are constant for the
>> >     lifetime of a specific document instance.  In otherwords, if I
>> >     process a page and start using it, depending upon blank node names
>> >     like '_:123' , that designator will refer to the same node at
>> >     least until the next time the page is processed.  We should make
>> >     this explicit if it is true.
>> >
>> 
>>> If I understand well what you say then I think I disagree. So here is how I understand: if I look at an RDFa page today and run a javascript with the API and I get _:123 as an identifier for a particular bnode, is it true that if I run the same javascript on the same page tomorrow, will I get _:123 as an identifier for the same bnode? If this is what you ask then my answer is no. There is absolutely no reason for that, _:123 is not a stable and permanent identifier for a node, it is only a temporary identifier at a particular run. It is a perfectly valid implementation of bnodes to use random identifiers, with the only requirement that two different bnodes should have different identifiers. (In fact, RDFLib explicitly runs a random generator to generate a bnode id to avoid giving the false impression that these are stable ID-s.) 
>> 
> 
[snip]

> Agreed.  However, that unique number would be persistent for the life of the current document.rdfa object, right?

Yes, that is correct.

Ivan


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