Compiling CASE

[Rob MacLachlan <RAM@C.CS.CMU.EDU>]

    Date: Thursday, 9 April 1987  10:08-EDT
    From: Guy Steele <gls at Think.COM>
    To:   Masinter.pa at xerox.com, common-lisp at sail.stanford.edu
    Re:   Compiling CASE

        Date: 8 Apr 87 14:56 PDT
        From: Masinter.pa@xerox.com

        It is an error to redefine *any* of the built-in symbols of
        Common Lisp, whether they are macros, special forms, or
        functions.

    I can't find, offhand, where in CLtL it says that.
    Can you give a reference?  Or is this a proposed cleanup?

This is part of my proposal to the compiler cleanup committee,
although I think others have arrived at the same interpretation
before.  This really seems pretty obvious if you choose to make
"correct program" synonomous with "portable program", since programs
that attempt to redefine parts of the language are apt to break the
system, and in any case won't coexist in the same lisp environment.

  Rob