p:step

A step looks like:

  step := ($kind, with-input*, with-output*)

Where $kind identifies the kind of process. That must either match the
name of some in-scope p:pipeline elment or match one of an
implementation-defined list of known process types.

  with-input := ($name, $from, $href, {any content})

The valid names depend on the $kind of step. Each can either come from
the output of some other step or input (in which case the $from must
match one of those labels) or from a URI or from content. It must have
exactly one of those.

  with-output := ($name, $label)

The valid names depend on the $kind of step. Each output has a label
by which other steps can refer to that stream.

                                        Be seeing you,
                                          norm

-- 
Norman Walsh
XML Standards Architect
Sun Microsystems, Inc.