Re: step must contain only a signature

Well, no doubt you've been laughing in your boots at me.  But I am  
finally able to answer my own question.  Indeed, I have the inputs and  
outputs wrong.  The problem is my ability (or rather inability) to  
comprehend the syntax of the spec.  I got the elements and attributes  
and their names all confused.  Here's what this is supposed to look  
like:

<p:declare-step xmlns:p="http://www.w3.org/ns/xproc" name="main">
     <p:input port="source" primary="true">
         <p:document href="BookStore.xml"/>
     </p:input>
     <p:output port="result"/>
     <p:delete match="/BookStore/Book/Title"/>
</p:declare-step>

And this works as expected.

James Garriss
http://garriss.blogspot.com

On Sep 12, 2008, at 12:22 PM, James Garriss wrote:

> I'm trying to write some simple pipelines with XProc.  I seem to get  
> this error frequently for various steps (swap out <p:delete> for  
> whatever step I'm using):
>
> Pipeline failed: org.xproc.XProcException: A p:delete step must  
> contain only a signature.
>
> What is this error trying to tell me?  I suspect it's telling me I  
> have the wrong number of inputs and outputs, but I don't quite get  
> what I'm missing (or adding).
>
> For grins, here's my pipeline:
>
> <p:declare-step xmlns:p="http://www.w3.org/ns/xproc" name="main">
>     <p:input port="source" primary="true">
>         <p:document href="BookStore.xml"/>
>     </p:input>
>     <p:output port="result"/>
>     <p:pipeline>
>         <p:delete>
>             <p:option name="BookStore/Book/Title" required="'false'"/>
>         </p:delete>
>     </p:pipeline>
> </p:declare-step>
>
> TIA,
>
> James Garriss
> http://garriss.blogspot.com
>