Shorthand XPointers can't be streamed

The fact that an element can be identified by a child that is a
schema-determined ID makes it impossible to search for a match in
a fully streaming manner.

For example, if the <id> element is of schema type ID, then in

   ... millions of child elements ...

a processor that is asked to return the "chapter1" element will have
to buffer the millions of child elements.  Worse, it would have to
buffer them even if <foo> turned out not to have an <id> child with
the right value.

A processor capable of schema type analysis may be able to optimise
this (e.g. an element that does not allow a child that can be of ID
type, and which is known to be valid, cannot have such an ID), but
this requires a lot of work.

-- Richard

Received on Friday, 21 March 2003 11:01:13 UTC