RE: A (hopefully comprehensive) versioning proposal

The proposal talks mainly about new or unrecognized steps, but what if
V2 introduces a new non-step construct, such as in the examples below:

<p:pipeline>
  <p:include href="..."/>

  <p:identity/>
</p:pipeline>

Worse, there may be new constructs that affect the dependency graph:

<p:identity>
  <p:input port="source">
    <p:big-pipe step="..." port="..."/>
  </p:input>
</p:identity>

or

<p:identity>
  <p:depends-on>
    <p:pipe step="..."/>
  </p:depends-on>
</p:identity>

The proposed strategy of marking the steps as invalid works well in the
first example, but not that well in the other two, because a V1
processor does not know what p:big-pipe and p:depends-on mean. Even if
you wrap the identity steps from in p:choose, a V1 processor can never
establish correct dependency graph.

I guess the only safe solution to this is to use "use-when" here.

Regards,
Vojtech

Received on Friday, 16 October 2009 12:43:46 UTC