Dictionary syntax proposal

After a good XDI Core editing session with Joseph tonight, we made the executive decision to adopt the dictionary definition syntax proposal discussed briefly on the last few telecons—namely, to use + syntax instead of $( ) syntax. I have updated the Graph Model Structure wiki page accordingly:

   https://wiki.oasis-open.org/xdi/GraphModelStructure

For the record, the reasons are:

$( ) syntax was the only vestige of our former syntax that depended heavily on cross-references.

I$( ) syntax is also the only syntax that required a prefix before a bracketing symbol (which makes it particularly complicated); all of the new bracketing symbol syntaxes we adopted do not use a prefix context symbol.

+ syntax is much simpler and can accomplish everything that $( ) syntax could.

Leaving $( ) syntax undefined means it is available to define once we get to the XDI query language (for which I suspect it might be needed).

The rule with using + syntax for dictionary defintions is that the + symbol is BY ITSELF the dictionary definition context. Thus to define any entity or attribute, just put it in that context. Examples:

Entity singleton: +passport   Definition: ++passport

Attribute singleton:  <+tel>    Definition:  +<+tel>

XDI authorities can create their own personal, legal, or general dictionary namespaces spaces by prefixing their own XDI addresses with +. So, for example, if Neustar had its own definition of +<+tel>, the definition would be (using Neustar's cloud name):

           +@neustar+<+tel>

Then, once Neustar had defined this, I could use an instance of a Neustar telephone number like this:

            =drummond+@neustar<+tel>

Any thoughts before Joseph and I write this into XDI Core 1.0 WD01?

=Drummond