[R6RS] modules

[Richard Kelsey]

   Date: Thu, 26 Aug 2004 14:32:03 -0500 (EST)
   From: "R. Kent Dybvig" <dyb at cs.indiana.edu>

   Unfortunately, the problems that arise with possible implicit export
   names appearing in syntax objects in more general macros also arise
   with syntax-rules.  Thus, the analysis is still complex, potentially
   expensive, and conservative.

Is it overly conservative to use the set of names that appear
on the right hand side of a rule but do not appear on the left
hand side?  It certainly is neither complex nor expensive.  As
a programmer I would definitely prefer that to having to list
the implicit exports by hand.

This is about enabling optimizations, isn't it?  I really don't
want to require people who don't care about the efficiency gains
to have to take the trouble to list the implicit exports.  Make
it optional.  Those that care can do the work and those that don't
can ignore the issue.  In the absence of a declaration the
implementator can put as much or as little effort as they like
into constructing the list of potential exports.

                                         -Richard