Re: Do pipelines have ports?

In 2:1:  Steps have ³ports² into which inputs and outputs are connected.
In 2:2:  The input ports declared on a step are its declared inputs.
In 2:3:  Each step may have one input port designated as the primary input
port and one output port designated as the primary output port.
In 2:4:  Steps are connected together by their input ports and output ports.
In 5:1:  A p:input identifies an input port for a step.

It¹s pretty clear that steps have ports.  It¹s not so clear (at least to me)
that pipelines have ports (hence my question below).  Now it¹s certainly
clear that pipelines have inputs/outputs, but once the WD starts talking
about ports (in the middle of 2:1), it only refers to steps having ports.
Maybe it should be more clear that pipelines also have ports?

The closest thing I have found is this, an indirect reference in section 2:
A pipeline is a set of connected steps, with outputs of one step flowing
into inputs of another.] A pipeline is itself a step.

Thanks for your help, Jeni!

James Garriss
http://garriss.blogspot.com




From: Jeni Tennison <jeni@jenitennison.com>
Date: Thu, 18 Sep 2008 22:02:12 +0100
To: James Garriss <james@garriss.org>
Cc: XProc Dev <xproc-dev@w3.org>
Subject: Re: Do pipelines have ports?

James,

> Is it correct to say that pipelines have ports as well, given an
> example such as this?
>
> <p:declare-step xmlns:p="http://www.w3.org/ns/xproc">
>     <p:input port="source">
>         <p:document href="BookStore.xml"/>
>     </p:input>
>     <p:output port="result"/>
>     <p:identity/>
> </p:declare-step>
>
> If not, what do you call them?


Absolutely. And if you ever give that step a type, then you can invoke
it as a step in another pipeline in exactly the same way you can the
built-in steps.

Jeni
-- 
Jeni Tennison
http://www.jenitennison.com