Re: Alternate "parameters" draft

/ ht@inf.ed.ac.uk (Henry S. Thompson) was heard to say:
| I have an alternate proposal, which I believe is both much simpler to
| explain and to implement, and which provides all the functionality of
| the current 'alternative' [2]:
|
|  To the _status quo_ (inherited, scoped, individual parameter
|  bindings, per [1] as of 10 May), simply add a single new element,
|  let's call it p:parameters, allowed once only in all steps (including

Why only once?

|  containers), content model as of p:input, that is
|
|  (p:inline|p:document|p:pipe)+
|
|  Contents should be a sequence of c:parameters documents, containing
|  c:parameter*.
|
|  Parameter semantics are unchanged from [1] except that we treat the
|  c:parameter name-value pairs as if they were p:parameter name-value
|  pairs on the step, occuring _before_ any explicit p:parameter
|  elements there.

With the proviso that local p:parameters override any specified in the
p:paramters input rather than being an error (as two explicit
p:parameter elements would be).

| That's it -- consistent inheritance and scoping, but the ability to
| construct, target and manipulate groups of parameter bindings.  Jeni,
| Norm -- is there anything you _can't_ do with this mechanism that you
| could do with [2]?

It doesn't solve one fundamental problem with the status quo which is
that all steps still always see all the parameters.

Given:

<p:pipeline>
  ...
  <p:xslt name="t1"/>
  ...
  <p:xslt name="t2"/>
  ...
</p:pipeline>

There's no way for me to pass a parameter "foo" to the pipeline such
that only t1 will see it.

                                        Be seeing you,
                                          norm

-- 
Norman Walsh <ndw@nwalsh.com> | In a universe of electrons and selfish
http://nwalsh.com/            | genes, blind physical forces and
                              | genetic replication, some people are
                              | going to get hurt, other people are
                              | going to get lucky, and you won't find
                              | any rhyme or reason in it, nor any
                              | justice.--Richard Dawkins