Re: Well Behaved RDF - Taming Blank Nodes, etc.

On Dec 13, 2012, at 12:42 , David Booth wrote:
[snip]
> 
>> 
>> The restriction of "no labels" is not just about "no cycles" - it's 
>> things that are not tree-like:
>> 
>> :x1 :p _:a .
>> :x2 :q _:a .
> 
> Yes, excellent example.  I explained to Pat in
> http://lists.w3.org/Archives/Public/semantic-web/2012Dec/0040.html
> why I chose the "no labels" restriction instead, but I'm open to
> considering either.
> 


I think it would still be better to explain these things in a syntax independent way. After all, I may want to use JSON-LD or RDFa...

Distilling the various mails and concentrating on bnodes only, what seems to be the pattern is 

- bnodes can appear in at most one triple as an object
- there can be no cycle in the graphs involving bnodes

Would that suffice as a more formal definition?

Ivan


----
Ivan Herman, W3C Semantic Web Activity Lead
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