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RE: Why do we still have p:parameters step ?

From: <vojtech.toman@emc.com>
Date: Tue, 23 Nov 2010 03:23:44 -0500
Message-ID: <997C307BEB90984EBE935699389EC41C02BC271A@CORPUSMX70C.corp.emc.com>
To: <public-xml-processing-model-wg@w3.org>
You are right, with p:identity you can do almost what you can with p:parameters. I say almost, because with p:parameters you can also do things like:



  <p:input port=”parameters”>

    <p:pipe step=”…” port=”…”/>


  <p:with-param name=”par” port=”parameters” select=”…”/>



Including p:with-param is something that you cannot do with p:identity.


There is also a potential difference between p:identity and p:parameters that the output of p:identity is just a simple identity. If you pass a c:param-set document to it, you get a c:param-set on the output, and  if you pass a sequence of c:param documents, you get a sequence of c:param documents. Whether you get a c:param-set document or a sequence of c:param document (or a mixture of both) is implementation-dependent in this case:


<p:declare-step name=”main”>

  <p:input port=”parameters” kind=”parameter”/>

  <p:output port=”result” sequence=”true”/>



    <p:input port=”source”>

      <p:pipe step=”main” port=”parameters”/>





With p:parameters, you are always guaranteed  to get a single c:param-set document which may be important if you want to query the parameters using XPath etc.


But I agree that for the simple situations, using p:identity is often much easier than p:parameters.





Vojtech Toman

Consultant Software Engineer

EMC | Information Intelligence Group





From: public-xml-processing-model-wg-request@w3.org [mailto:public-xml-processing-model-wg-request@w3.org] On Behalf Of Innovimax SARL
Sent: Tuesday, November 23, 2010 8:59 AM
To: XProc WG
Subject: Why do we still have p:parameters step ?


Dear all,

It seems that we can do everything we need to handle parameter port through p:identity or even simple connection to the read

So I was wondering what was the point of still having p:parameters step ?

It seems that this one is not needed at all

Am I wrong here ?


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Received on Tuesday, 23 November 2010 08:25:20 UTC

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