[Bug 24547] Streamability of accumulators, missing initial-value

https://www.w3.org/Bugs/Public/show_bug.cgi?id=24547

--- Comment #2 from Michael Kay <mike@saxonica.com> ---
Looking at the rules for accumulators, I think it is necessary for the
initial-value and the new-value expressions to be both grounded and motionless.
We can't have the current value of the accumulator being a streamed node.

Furthermore, to assess the posture and sweep of these expressions, we need to
know the context item type and context posture for their evaluation. The
context item type for initial-value is document-node(), and for new-value it is
the "match type" of the pattern as defined in 19.3. I think we can safely take
the context posture for both as "striding".

I'm not convinced that the context item for evaluation of the initial-value of
an accumulator should be the initial context item used for global variables, as
currently stated. It seems to make much more sense to use the document node of
the document for which the accumulator is being evaluated; or perhaps even an
absent focus.

Regarding error XTSE0548, we need to rethink this in the light of the
separation of initial context item from initial input sequence. Since these can
now be different, the remaining error is that the initial context item should
not be a streamed node, but that's not really an error in the stylesheet, it's
something within the scope of the API.

-- 
You are receiving this mail because:
You are the QA Contact for the bug.

Received on Friday, 21 February 2014 15:52:20 UTC