Based on that, I think that the make-namespace-anchor is what I need - I tried it and it works.  It sounds like that would allow my constraints to contain local variables, which is a good thing.  [Note, my current examples don't do that, but I will come up with something that does.]<br> <br><div class="gmail_quote">On Thu, Jul 3, 2008 at 1:47 PM, Eli Barzilay <<a href="mailto:eli@barzilay.org">eli@barzilay.org</a>> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> <div class="Ih2E3d">On Jul  3, Doug Williams wrote:<br> > The (namespace-require 'scheme/base) worked fine.  Is there any<br> > advantage/disadvantage to using the private namespace as Eli<br> > suggested?<br> <br> </div>It depends on what you need.  The `namespace-require' modifies the<br> global namespace, the `make-base-namespace' creates a private<br> namespace that you can use for a single purpose, and the anchor makes<br> sure that the evaluation happens in the same language your module is<br> written in as well as making local bindings accessible in code that<br> you evaluate.<br> <font color="#888888"><br> --<br> </font><div><div></div><div class="Wj3C7c">          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:<br>                  <a href="http://www.barzilay.org/" target="_blank">http://www.barzilay.org/</a>                 Maze is Life!<br> </div></div></blockquote></div><br>