Note: updated syntax example for you to play with

After Joseph's email today (suggesting using only single character symbols) and my working on the ABNF tonight and realizing that it would be best not to try to overload $ as the dictionary context symbol, this means we now have five syntax symbols to choose. I have updated https://wiki.oasis-open.org/xdi/XdiSyntaxExamples to show this.

An updated example model is below. If you want to play with this before or during tomorrow's telecon, just cut and paste it into a word processor and do a search/replace on your choices for each of the 5 symbols to help you decide what the most readable syntax is.

Attribute symbol: &
Singleton symbol: |
Definition symbol: <
Literal symbol: :
Ordered instance (array index) symbol: #

=markus|&+email/$ref/
   =markus&+email!9876
=markus+home|&+email/$ref/
   =markus&+email!5432
=markus+work|&+email/$ref/
   =markus&+email!9876
=markus&+email!5432:/:/
   "ms@example.com"
=markus&+email!9876:/:/
   "markus@example.net"
=markus&+email!9876|&$t:/:/
   "2013-04-11T10:11:12Z"
=markus+address!4567&+street#1:/:/
   "123 Main St"
=markus+address!4567&+street#2:/:/
   "Apt 23"
=markus+address!4567|&+city:/:/
   "Vienna"
=markus+address!4567|&+country:/:/
   "Austria"
=markus+address!4567|&$t:/:/
   "2013-04-11T10:11:12Z"
<&+email/$is+/
   $string
<@example<&+email&$xbnf#1:/:/
   "1*DIGIT '@example.com'"

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