Hannu Krosing wrote:
> Is it just that in you _can't_ use Xpath on fragments, and you _need_ to
> pass full documents to Xpath ?
>
> At least this is my reading of Xpath standard.
>
>
I think that's possibly overstating it., unless I have missed something
(W3 standards are sometimes not much more clear than the SQL standards ;-( )
For instance, there's this, that implies at least that the tree might
not be a document:
A "/" at the beginning of a path expression is an abbreviation for the initial step fn:root(self::node()) treat as
document-node()/ (however, if the "/" is the entire path expression, the trailing "/" is omitted from the
expansion.)The effect of this initial step is to begin the path at the root node of the tree that contains the
contextnode. If the context item is not a node, a type error is raised [err:XPTY0020]. At evaluation time, if the
rootnode above the context node is not a document node, a dynamic error is raised [err:XPDY0050].
The problem is that we certainly do have to provide a context node (the
standard is clear about that), and unless we want to convert a
non-document to a node-set as James suggested and then apply the xpath
expression to each node in the node-set, we have no way of sanely
specifying the context node.
cheers
andrew
