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Re: need for quoting in Lisp

    Date: 28 Oct 1985 16:07-EST 
    From: Barak.Pearlmutter@G.CS.CMU.EDU
								   ... To
    illustrate very concretely, imagine a Schemelike language which is NOT
    it's own metalanguage, in which there are no macros.  For any
    construct, we can tell unambiguously whether we have code or data
    in our hands, and hence quoting will be unnecessary.


To Mr. Pearlmutter's excellent exposition I would like to add the observation
that, 25 years ago, LISP was originally conceived in exactly these terms.
Allow me to add to the table of examples the representation as LISP
"M-expressions" ("meta-expressions"):

	    Regular Scheme				Scheme0			M-expressions

     (car (append x y))			(car (append x y))		car[append[x; y]]

     (car (quote (append x y)))		(car [APPEND X Y])		car[(APPEND X Y)]

     (append (f x) (g (quote y))	(append (f x) (g Y) [H Z])	append[f[x]; g[Y]; (H Z)]
	     (quote (h z)))