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Control characters in # macro.

    Date: 10 September 1979 03:58-EDT
    From: Alan Bawden <ALAN at MIT-AI>
    The MacLisp #/C would return 303 not 3 since thats the bit
    that is set if you try and hack keyboards with control and
    meta.  MacLisp also has a #^<char> that uppercases <char>
    and then xors it with 100 so that #^C is 3 (as is #^c) and
    #^? is rubout. This is sometimes usefull in MacLisp but
    never in LispMachine lisp, and I don't know about NIL. 

Well, this isn't right.  One of the motivations for using #/ and #\ is
to be independent of the character set of the particular system being used.
Clearly, #\RUBOUT should read as 207 on the Lisp Machine and in QCMP, and
as 177 in MacLisp.  The same should be true of "control" characters.  In
MacLisp, though, they could read as ascii characters or in the ITS 12-bit
character set.