Saxon

The specification of the fn:transform() function does not allow the principal source document to be supplied in streamable form (for example as a URI of a document to be read using streaming).

We are developing a test driver that relies on fn:transform() to invoke transformations, so this is a serious limitation.

I'm fixing this by adding an optional parameter source-location="uri" that can be used in place of the source-node parameter; its value is a URI. The XML document located at the supplied URI is used as the initial match selection for an apply-templates invocation of the stylesheet. The option may be used whether or not streaming is required.