[Bug 5400] Clarification of deref() needed

http://www.w3.org/Bugs/Public/show_bug.cgi?id=5400





------- Comment #4 from johnarwe@us.ibm.com  2008-02-13 00:36 -------
from: passed to     deref() function
to  : passed to the deref() function

(similarly on O=/returned by)

fwiw, this section seems likely to give outside readers problems.  I anticipate
them trying to reconcile it with the behavior required of model validators,
which is different.  I am willing to let the outside review process force us
there.  I will present the following proposal however, so if the wg as a whole
anticipates the same problem and wants to fix it now, or we punt now and
demonstrate it later via the review process, we have a start at addressing it.

Add the following, immediately after the heading:
Note:
This note is non-normative.  This section describes the behavior required for a
general XPath 1.0 deref() library function, and as such exhibits several
significant differences from the behavior required to validate SML references
during model validation.  First, it can be used to successfully process
instance documents whose SML model validity is unknown or invalid, although the
results in this case may not be interoperable.  Second, since XPath 1.0 defines
no way for a function to signal erroneous input to its caller, the behavior
here is specified to return results for SML references that do not obey all of
the validity rules, e.g. a reference whose XPath expression evaluates to more
than one node.  As described in this section, such a function would be
insufficient to check the validity of SML references.

Received on Wednesday, 13 February 2008 00:36:56 UTC