[racket] conditional includes in a Scribble file

Here's a non-working example:
---------
#lang scribble/base

@(define edition (make-parameter "default"))

@(edition "teacher")

@(define (itemlist* . args)
  (apply itemlist (filter item? args)))

@(define (only-edition v text)
  (when (equal? (edition) v)
    text))

@title{Example}

@section{This is a section}

And it appears in all versions.

@only-edition["teacher"]{
@section{This is another section}

And it should only appear in the teacher edition.
}
-----

As is, it says @only-edition expects 2 arguments and gets too many. If
you put a dot in front of text, it says it's not valid (something
about a pre-part). If you change text in the body to (values text) it
says that the context expects a single value and got 4.

Basically I need to be able to consume and output (or not) an
arbitrary sequence of Scribble.

Todd
On Wed, Jun 29, 2011 at 9:54 AM, Matthew Flatt <mflatt at cs.utah.edu> wrote:
> At Wed, 29 Jun 2011 09:47:16 -0400, "Todd O'Bryan" wrote:
>> Any thoughts on the second problem--how to unwrap a (list el1 el2 el3
>> ...) so that Scribble interprets it as el1 el2 el3 ... ?
>
> I'm not sure I understand. Can you give me an example of the problem?
>
>