View source for XProc New Steps

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= New Simple and Compound Steps =

'''TODO (you can help!):'''
* See http://exproc.org/proposed/steps/ and make entries below
* See http://xmlcalabash.com/docs/reference/ (looking at extension steps) and make entries below

== Sorting ==

Should we have a <code>p:sort</code>?  What would it look like?
* <code>xsl:sort</code> provides one possible model—how much would we use?

== Validation with error ==

Is there a way to have validation not require <code>try</code>/<code>catch</code> to access error messages?  So that we could stream validation?
* Try-catch cannot be streamed. If there ''is'' an error, however late in the day, there is nothing on the primary <code>output</code>

== Map-reduce ==
Some kind of support for scatter-gather/map-reduce/whatever-you-like to call it
* Does this need anything we don’t have already?

== Iterate until condition ==
Repeat a step (group?) until some XPath expression is satisfied, feeding its output back as input after the first go-around
* Reference <code>xsl:iterate</code>
* Special built-in support for iterate to fixed-point?
** iterate-to-fixed-point already implemented as an extension step in Calabash: <code>ex:until-unchanged</code>


== Dynamic pipeline execution ==
Run a pipeline whose XML representation is input

:Can you elaborate? <br>[[User:Arogers|Zearin (Arogers)]] 15:53, 11 October 2012 (UTC)

== Long-form <code>viewport</code> ==
With an intrinsic built-in switch

== E-mail ==
Steps to handle SMTP, and send e-mail messages

== URI manipulation==
a step to set the base URI of a document
<pre>

<p:declare-step type="p:set-base-uri">
     <p:input port="source"/>
     <p:output port="result"/>
     <p:option name="base-uri" required="true"/>
</p:declare-step>

</pre>

== Compound step ==

convenient to have a p:if compound step

<pre>

<p:if 
      name? = NCName 
      test? = XPathExpression>
     ( p:xpath-context?,
       subpipeline) 
  </p:if>

</pre>

could be a degenerate case of p:choose ?

== Iteration ==

* a step to iterate over 2 sequences, like a p:for-each but with 2 iteration sources that are iterated in parallel (1st doc of each, 2nd doc of each, etc). (can be covered by p:pack / p:for-each / p:unwrap)

== input == 
* a step that accepts (and waits) for external input

== resource manager step ==
* provide step for overriding URI - assumes the existence of some kind of resource manager

{{XProc}}

[[Category:XProc]]