Re: Syntax Turtle used for graphs

Hello, 

On 29 Sep 2011, at 13:25, Andy Seaborne wrote:

> Can we change the title to not imply that graph identification is part of Turtle?  Why not a separate langauge using the same langauge?  A document of a graph can be read to get a stream of triples; a compound document can't be.

+1, it would be really nice for Turtle to be left as is, as a document of triples. 

> 
> Style wise - there is packing a collection of graphs together (@graph emphasises this), writing/reading named grapg data (TriG emphasises this) and dump (N-Quads emphasises this).
> 
> I hope we have N-quads as standalone spec c.f. Turtle and N-triples.

Another +1

> [[
> Assumptions:
> 
> Alignment with SPARQL is more important then alignment with N3.
> 
> The community does not have a lot of investment in TriG syntax.
> 
> The community has some investment in N-Quads.
> ]]
> 
> While the community may not have a *lot* of investment in TriG syntax it is out there and used.  I haven't seen or heard any serious faults with the general design (yes - there are specific issues).
> 
> To switch to another format needs a positive reason to switch even if the barrier is quite low.
> 
> Considerations:
> 
> Should "format X", a syntax based on Turtle used for graphs,
> 
> 1/ Have Turtle as a subset?
>   i.e. is a valid Turtle document a valid format X?
> 
> 2/ Have N-Quads as a subset?
> 
> I used to think (1) was important but I'm not so convinced any more.  A document of triples isn't a document about several sets of triples.

It would be nice "format X" to be distinguishable from the outset to be different from Turtle, and for it to always be quad based in nature. Personal experience in harvesting RDF documents from the web suggests that not every is that careful about setting the correct mime-type when putting data on the web. 

> 
> Possibilities for TriG-ish:
> 
> A/ TriG as is.
> 
> B/ TriG as is, but drop the uniqueness of the default graph and naming of graphs (does any system actually impose these conditions? why?).
> 
> C/ TriG+NQuads
>   Allow N-Quads outside {}
> 
> D/ TriG+Turtle
>  Allow un-enclosed Turtle for the default graph
>  (as well as or instead of {})
> 
> Note that C also means N-triples because N-triples is a subset of N-Quads.

Personally I would prefer for this not to be the case, and for N-Quads to mandate quads and not allow for triples on their own. 

Mischa

> 
> These are only general directions - whatever we do there are techncial issues like treatment of trailing DOTs.
> 
> 
> 	Andy
> 
> 
> 
> 

___________________________________
Mischa Tuffield PhD
Email: mischa.tuffield@garlik.com
Homepage - http://mmt.me.uk/
+44(0)208 439 8200  http://www.garlik.com/
Registered in England and Wales 535 7233 VAT # 849 0517 11
Registered office: Thames House, Portsmouth Road, Esher, Surrey, KT10 9AD