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Rational operations of one argument

    Date: 31 July 1981 03:31-EDT
    From: David A. Moon <Moon at MIT-MC>
    Subject: Inconsistency of 1-argument QUOTIENT with //,//$
    This appears to be a documented feature, at least in the red manual.
    I wonder why?  Perhaps it's a (possibly spurious) analogy with the
    difference between DIFFERENCE and - ?
GLS has already quite satisfactorily given the reply to this query,
(esp. w.r.t. reasons behind the two different extensions, and the
irrelevance of hardware considerations), but I'd like to add the 
historical note that this question was really only faced when CGOL
started to get some usage (when? I'm not sure, but maybe in 1973), and
PRATT was instrumental in maintaing the difference (no pun intended) 
between the two extensions.  Thus, e.g., DIFFERENCE of one argument 
remained the identity function, instead becoming the group inverse 
operator, whereas "-" of one argument was defined to become the 
negation operation.