On 03/12/2011 23:27, David Lee wrote:
There are other objections the WG might want to consider: Assigning a meaning to constructs that are currently disallowedI'm not suggesting "{}" is a 'no-op' I'm suggesting it parses equivalent to {()} Maybe in the next week or two I'll study the BNF in more detail and make a formal suggestion as per Liam's suggestion for XQuery 3.0So far I haven't seen any reason why it would be either 1) Ambiguous 2) Cause parser confusion 3) Cause reader confusion 4) Cause 'unexpected' things to happen
(a) can make it more difficult to produce good diagnostics for queries that are actually wrong (ultimately, you end up with the HTML5 situation where everything you write means something, so there are no compile-time errors, only run-time errors), and
(b) can "use up" syntactic space that might be needed in the future for new features. For example, one might want "{}" to represent an empty map - which is not necessarily inconsistent with this proposal, but in general, when you give a syntactic construct a meaning you remove the option of giving it a different meaning in the future.
Michael Kay Saxonica _______________________________________________ [email protected] http://x-query.com/mailman/listinfo/talk
