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re: Actually, I think this is bogus. The simple portable way to handle #, is to
    have the compiler use a a readtable which has ' defined as a readmacro like

Although several others have expressed an opion disagreeing with your
conjectured parallels between #, and #.,  I don't think anyone attempted
to rebut this suggestion adequately.

A couple months ago, there was extensive discussion about the inherently
ill-defined nature of #, but I can't seem to locate it in my mail file.
I sent out a couple of examples that would "break" in every Lisp I had
access to, either interpreted or compiled.  [If anyone still has a 
copy of that code, I would appreciate a copy sent back!  blame it on
NFS or Emacs dying at the wrong time, but I have lost my copy].

The problem lies in thinking -- as you are in the above suggestion -- 
that when compiling a file, a form will be read solely for the purpose of
converting it into executable code of some form.  Of course, a great deal 
of what is read at compile time is for exectution (read: evaluation by the 
interpreter) also.  Thus you cannot tinker with the definition of ' in the 
"compiler's readtable".  [Well, you _could_  muck with it if the semantics 
of QUOTE were clearly in the MAY-COPY:ALWAYS category, for then the 
interpreter would simply pre-process any quoted forms, removing any
extraneous wrappers in the returned copy].

-- JonL --