Date: Sat, 29 Mar 2008 10:31:23 -0400 (EDT)
   From: AndrevanTonder <xxxxxx@het.brown.edu>

   Whether one should follow R6RS and also (re-)export underscore _ as
   part of this library is less clear to me.  Maybe it should be up to
   the author whether the R6RS special underscore treatment should be
   followed by the SYNTAX-RULES defined in this library.  I think it
   may be hard to avoid in an R6RS-based implementation.

Personally I find the whole underscore business absurd.  However, it
occurs to me that there is no reason to use SRFI 46 with the R6RS, so
this is all moot.