[plt-scheme] units and sigs and files

When writing MzScheme libraries, is there a way to get the goodness of
units and sigs without splitting the library into three separate files
(<m>.ss, <m>-unit.ss, and <m>-sig.ss)?

I've already converted some of my libraries from one-file-per-library to
one-collection-and-four-files-per-library.  But this kind of packaging
seems a little cumbersome and redundant for the usual case of libraries,
so I'm wondering if I'm missing a simplification.

-- 
                                             http://www.neilvandyke.org/