Pascal Costanza  <pc@p-cos.net> wrote:
+---------------
| A further comment: A macro is a local source-to-source transformation, 
| which means that global issues cannot be taken into account which can be 
| a limitation. (One attempt to break out of these limitations were 
| "Macros that reach out and touch somewhere" - see 
| http://www2.parc.com/csl/groups/sda/publications/papers/Kiczales-Macros91/for-web.pdf 
| )
+---------------

Another attempt, although it may not be immediately obvious that it's
related to that, is recent work on access to lexical environments such
as the tutorial that Duane Rettig just gave at ILC 2005 <http://www.
international-lisp-conference.org/tutorials.html#making_environments_
accessible_in_common_lisp>. When macros can reliably examine their
lexical environment, a number of the global issues can be directly
addressed. And if *write* access to the lexical environment is provided,
especially the ability to mutate portions of the environment "above" one,
then many [though not all] of the other global issues can be addressed
as well.


-Rob

-----
Rob Warnock			<rpw3@rpw3.org>
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