Load .scm file from within define-void-function

[Urs Liska]

I have written a function that abstracts the loading of include files 
(by performing different path checks, offering a dot-notation interface 
and ensuring that files are included only once).
The actual loading is done through ly:parser-include-string using an 
"\include" statement.

Now I'd like to extend the function to be able to load either LilyPond 
or Scheme files. (It will be passed the name without extension, and 
depending on what file type exists on disk it would do the right thing.

However, AFAICS I can only use (use-modules) as a top-level expression 
and not within a Scheme function. OTOH I can't use the "\include" 
approach either because then the file would be interpreted as LilyPond - 
which of course fails.

So: Is it possible to load a Scheme module from within a 
(define-void-function) ?

Any hint or solution would be greatly appreciated.
Urs