Subject: Re: "Wrong" results from _Common LISPcraft_ scope example
From: Erik Naggum <>
Date: 1998/09/27
Newsgroups: comp.lang.lisp
Message-ID: <>

* Erik Naggum <>
| the reasonable behavior is to assume that a variable that is not closed
| over lexically has a special binding.

* (Rainer Joswig)
| I would rather not assume that.  It would introduce unnecessary errors in
| interactive use.  Implementations like ACL, LW, MCL, Genera are doing it
| "right".  AFAIK, only CMU CL is different.

  CMUCL does not _assume_ that, it actively goes ahead and declares it
  special.  to me, that is a hell of a difference.

  when is it legitimate, then, to _assume_ special bindings for undeclared
  variables?  I thought it would be sufficiently clear that it would be
  under evaluation and compilation.  when else would it be meaningful to
  discuss this?  i.e., SUM in SUM-AVERAGE is assumed to have special
  binding.  what else would it be when it is not closed over lexically?