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issue SHARP-COMMA-CONFUSION
- To: masinter.pa@Xerox.COM
- Subject: issue SHARP-COMMA-CONFUSION
- From: Jon L White <jonl@lucid.com>
- Date: Tue, 10 Jan 89 04:02:47 PST
- Cc: cl-compiler@sail.stanford.edu
- In-reply-to: masinter.pa@Xerox.COM's message of 5 Jan 89 21:33 PST <890105-213421-186@Xerox>
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 --