Hi all,

I am wondering if and how it might be possible to catch all unmarked
paragraphs in a TeX file and pass them into Lua. So, in the following
example, each of the first three unmarked paragraphs would be passed to the
Lua function "process_paragraph" for optional processing, but the fourth
paragraph between \startmarkedparagraph...\stopmarkedparagraph would not be
passed to "process_paragraph".

I want the Lua function to be able to eat each of the first three unmarked
paragraphs and optionally write some processed version back out to be
typeset, but there should be the possibility that none of the paragraphs are
typeset at all.

In the latter case that no text is to be typeset at all, is there a way to
prevent ConTeXt/LuaTeX from creating an empty PDF?

\startluacode

def process_paragragh (par)
   -- Some magic here...
   -- Maybe a context (processed_par) to typeset the processed paragraph...
end

\stopluacode

\starttext

Thus, I came to the conclusion that the designer of a new
system must not only be the implementer and first
large||scale user; the designer should also write the first
user manual.
\startitemize
\item One
\item Two
\item Three
\stopitemize

The separation of any of these four components would have
hurt \TeX\ significantly. If I had not participated fully in
all these activities, literally hundreds of improvements
would never have been made, because I would never have
thought of them or perceived why they were important.

But a system cannot be successful if it is too strongly
influenced by a single person. Once the initial design is
complete and fairly robust, the real test begins as people
with many different viewpoints undertake their own
experiments.

\startmarkedparagraph
Thus, I came to the conclusion that the designer of a new
system must not only be the implementer and first
large||scale user; the designer should also write the first
user manual.
\stopmarkedparagraph

\stoptext

Thanks,

Kevin