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

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:parameters>

  <p:input port=”parameters”>

    <p:pipe step=”…” port=”…”/>

  </p:input>

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

</p:parameters>

 

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:identity>

    <p:input port=”source”>

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

    </p:input>

  </p:identity>

</p:declare-step>

 

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

 

--

Vojtech Toman

Consultant Software Engineer

EMC | Information Intelligence Group

vojtech.toman@emc.com

http://developer.emc.com/xmltech


 

 

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 ?

Mohamed

-- 
Innovimax SARL
Consulting, Training & XML Development
9, impasse des Orteaux
75020 Paris
Tel : +33 9 52 475787
Fax : +33 1 4356 1746
http://www.innovimax.fr

RCS Paris 488.018.631
SARL au capital de 10.000 €