removing constraints

[Roman Cheplyaka]

Thank you all for explaining. I confused Ratio and Rational, as I always
do, hence my surprise.

On 09/01/15 18:02, David Feuer wrote:
> Yes, that is what I was referring to. I don't remember where it was, but
> IRC is a possibility. The basic problem is that if you consider the
> types that would make sense as numerators and denominators for a ratio,
> and you consider the instances of Integral, then their intersection
> turns out to be, to a close approximation, {Integer}. The problem
> Brandon Allbery points out restricts things on one side, while the
> peculiar constraint that Integral is a subclass of Real restricts things
> on the other.
> 
> On Jan 9, 2015 10:44 AM, "Brandon Allbery" <allbery.b at gmail.com
> <mailto:allbery.b at gmail.com>> wrote:
> 
>     On Fri, Jan 9, 2015 at 10:38 AM, Roman Cheplyaka <roma at ro-che.info
>     <mailto:roma at ro-che.info>> wrote:
> 
>         On 09/01/15 17:29, David Feuer wrote:
>         >> The other cases are more arguable.  For example the change to Data.Ratio
>         >> declares that the pair is kept in reduced form, but one could argue that
>         >> requiring that is no bad thing.
>         >
>         > Disagreed. However, some have argued convincingly that the Ratio type as
>         > it stands makes little sense anyway.
> 
>         [citation needed]
> 
> 
>     I believe this is referencing a past discussion (possibly on IRC)
>     where it was pointed out that Ratio is a type constructor, but the
>     only instance that makes any sense is Ratio Integer because any
>     bounded integral type will eventually (and usually rather quickly)
>     exceed the bounds and fail rather spectacularly given the lack of
>     exceptions on bounded-integral wraparound?
> 
>     -- 
>     brandon s allbery kf8nh                               sine nomine
>     associates
>     allbery.b at gmail.com <mailto:allbery.b at gmail.com>                    
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