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Re: My ideas about infinity in Scheme (revised)
Ken Dickey wrote:
> But computational infinities are not really numbers.
That's all a matter of definition. People used to think that
zero "is not really a number." Some may think that a number
is anything that obeys certain mathematical laws.
I think of the type "extended-exact-rational" as comprising
fractions plus 1/0 and -1/0. I think that extended set has some
nice properties, providing reasonable definitions for some
otherwise undefineds operation. On the other hand, some
operations, such as (+ 1/0 -1/0), remain undefined.
Aesthetically, I like having 1/0 and -1/0 as exact numbers.
Not being a mathematician, I won't express a strong opinion, though.
> BTW, as markers I would expect
> (eq? 1/0 1/0) -> #t
Likewise if they're viewed as exact numbers.