[plt-scheme] Wrapping non-PLT code in modules

Thanks everyone for the answers - "include" is exactly what I needed.  It
allows me to selectively provide procedures from the included file, which is
what I really wanted to do.

I have a related (and much less important) question.  Ideally, for this
wrapping of R5RS code that I'm doing, I'd like to be able to specify R5RS as
the language for these modules.  Using r5rs as a symbol didn't work for me,
and the docs don't seem to mention anything other than mzscheme as built-in.

So, I tried providing a relative path to collects/lang/r5rs.ss.  This failed
because of not having "provide" and "require" defined in that "language".
So I copied r5rs.ss and added "provide" and "require" to its provide
statement.  That worked!  Cool.  (I think.  I haven't run into any
show-stopping problems with it yet...)

My question is, is there a simple|recommended|obvious way to do this that
I've missed?

Anton