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Re: [Scheme-reports] Cycle detection problems: #442, #338, "equal?"

On Fri, 31 Aug 2012 11:21:18 -0400, John Cowan <cowan@x> said:

> John Boyle scripsit:
> ...
>> Actually, come to think of it, there is one fact about equal? that is true
>> for all non-cyclic structures that isn't true under unfolding: if (equal? a
>> b), then not (equal? (cons <something> a) b).  

> That's just a way of encoding the paradoxical fact that one plus infinity
> is still equal to infinity.

  Though "equal" in the previous sentence does not refer to the
  (usual) equality relation between numbers (but to a different
  relation).  Infinity is a funny thing...


Vassil Nikolov | Васил Николов | <vnikolov@x>

"Be careful how you fix what you don't understand."  (Brooks 2010, 185)

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