[XPath] implicit timezone

Can the implicit timezone be undefined?

The table in Appendix C.2 of XQuery would appear to suggest that it can, and
the implicit-timezone() function in F+O states that the function returns an
empty sequence if the implicit timezone is undefined. But there are many
operations that rely on knowing the implicit timezone, and do not define any
error condition if it is undefined.

I would suggest that (as with current date/time) we do not allow the
implicit timezone to be undefined. It makes life easier for everybody. This
would change the signature of the implicit-timezone() function.

I would also suggest that appendix C.2, in both XPath and XQuery, should
clarify which components of the dynamic context can be "undefined". I think
that only context item, position, and size can be undefined. Current
date/time and implicit timezone must be defined; the other components in the
dynamic context (that is: dynamic variables, available documents, available
collections) can be empty sets but they cannot be undefined.

Michael Kay

Received on Friday, 9 April 2004 13:03:40 UTC