Viewport

• From: Richard Tobin <richard@inf.ed.ac.uk>
• Date: Mon, 3 Dec 2007 16:07:03 +0000 (GMT)
• To: public-xml-processing-model-wg@w3.org
• Message-Id: <20071203160703.18C6329B128@macpro.inf.ed.ac.uk>

The description of p:viewport in the spec is not clear.

Initially it talks about "the result" and "the output" of p:viewport,
but ends with text cut and pasted from other subpipelines which have a
variable number of outputs.

It should say that a viewport has exactly one output.

It also needs to be clearer about the output from the subpipeline and
the output from the whole viewport step.  Conceptually, a viewport
*contains* a subpipeline and the document on the output port of the
viewport is constructed from the the documents on the output port of
the subpipeline.  But the syntax only has one output declaration.

In principle it seems reasonable for the output port of the
subpipeline to be a sequence: the selected input can reasonably be
replaced with more than one element or with nothing.  But the output
of the viewport itself is a single document regardless.

Is the output of the viewport always a primary output?  Or is it
only if the output of the subpipeline is?

-- Richard

Received on Monday, 3 December 2007 16:06:36 UTC