(dsssl) "Default" processing rule?

[MARK.WROTH@xxxxxxxxxxx (Wroth, Mark)]

How can I (simply) define a set of rules that will ignore everything
*except* an element that can be found at several levels?

Setting (default (empty-sosofo)) results in everything being ignored,
presumably because the parent elements of the one I want are not processing
their children.

For those familiar with DocBook, the basic DTD is an extension to DocBook,
and the element I want to process is the <programlisting>

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