Re: NIL and DEFCONSTANT [Gall: Bug Report]

[David A. Moon <Moon@SCRC-STONY-BROOK.ARPA>]

    Date:  Tue, 2 Apr 85 15:06 EST
    From:  Nick Gall <Gall@MIT-MULTICS.ARPA>

	    !section  20.1(last-1)        Nick Gall 85-03-19
	    !version  Digital Press 1984
	    !topic    Is nil declared by defconstant?

			...all constant symbols declared by DEFCONSTANT, such as NIL,
		  T, and PI.

	    If NIL is declared by DEFCONSTANT then it can legally be
	    redefined according to section 5.1.2(last):

			Constant symbols defined by DEFCONSTANT ... may be redefined,
		  if necessary, by using DEFCONSTANT again[].

	    Is such an interpretation correct?

	From: Moon
	I do not believe that system-supplied constants can legally be redefined.

    Is it that my interpretation is incorrect (and if so why?) or is
    it that the CLRM is incorrect (and if so how?).

The CLRM is not self-consistent.  As I said, I do not believe that system-supplied
constants can legally be redefined, so where the CLRM says or implies that they can
be it is wrong, in my opinion, and where it says or implies that they cannot be
it is not wrong.