Re: [xdi] Minutes: XDI TC Telecon Friday 2013-05-03

[Drummond Reed <drummond.reed@xdi.org>]

On Sun, May 5, 2013 at 2:05 PM, Joseph Boyle <planetwork@josephboyle.net> wrote:

I've started drafting at https://wiki.oasis-open.org/xdi/XdiAbnf/Discussion

Drummond, does multiple objects per S/P (in the 2-line display format or the flat JSON serialization) mean that one multiple-object statement can mix more than one of the 4 direct contextual statement types, or more than one of the 4 inverse contextual statement types? 

If I understand the question correctly: no. Every S/P predicate uniquely determines one of the context relationship types, i.e., <--context-->/() can only be used to make a direct-contextual statement, and
<--context-->/$is() can only be used to make an inverse contextual statement, etc.

Also, () is a possible object of a relational statement but is not included under the 'context' rule.  1*(context / "()") would allow repetition of () or of any other context for that matter. Should I just use 1*(context / "()" or something else for multiple objects?

() can only occur once as the object of a relational statement. And we shouldn't need "multiple contexts" either since the context rule can already include subcontexts.

 

On May 5, 2013, at 11:13 AM, Drummond Reed <drummond.reed@xdi.org> wrote:

On Sun, May 5, 2013 at 9:16 AM, Joseph Boyle <planetwork@josephboyle.net> wrote:

I will make the top-level production statement-list instead of xdi-graph, since a statement list is only one way of serializing a graph, along with at least the graph tree serialization. We want to be able to think of graphs as graphs independent of serialization.

Good point.

 

I am going to genericize the Statement ABNF so that it can generate as many as possible of the serializations when paired with ABNF for the specific syntax of each serialization.

Good plan.

 

For the serializations that allow multiple objects per single subject/predicate, we need rules for statements with multiple objects. Drummond, could you let me know which of the statement types in the Statement ABNF allow multiple objects?

Contextual and relational statements (and their inverses) allow for multiple XDI objects. Literal statements allow only one XDI object.