Derick Eddington wrote:
> With the previous revision which didn't support different file name
> extensions for different dialects, different dialects could not share
> the search paths environment variable because different dialects would
> be using the same extension and so a file for one dialect could
> unavoidably shadow a file for another dialect.  With different
> extensions, that problem doesn't exist and different dialects can
> share the environment variable.

OK, now I think I got it. Different extensions for implementations are
introduced not to be able to put different implementation-specific
libraries into the exact same folder (which was my objection), but to
resolve shadowing which may occur when SCHEME_LIB_PATH lists several paths.