On Fri, Jul 3, 2015 at 4:29 AM, Edi Weitz <edi@weitz.de> wrote:
On Fri, Jul 3, 2015 at 10:21 AM, Kenneth Tilton <ken@tiltontec.com> wrote:
> EQ, as you adroitly demonstrated, worries about all sorts of things,
> including a symbol's package.

Which is part of what has me confused.  Up until now I would have said
that the "problem" of EQ is that it doesn't worry about _enough_
things.  (EQ 3/4 3/4) is NIL because EQ doesn't bother to look "into"
the numbers (as EQL does) but just superficially checks their "pointer
identity".  And for symbols that's not the case?  Hmmm...


<cough> OK, I myself was at the wrong level of abstraction: EQ is not worrying about anything other than pointer identity. It is the behavior of intern and unintern that arranges for two symbols with the same name to be distinct objects if their packages vary.

-kt

--
Kenneth Tilton
54 Isle of Venice Dr
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@tiltonsalgebra


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