[Haskell-cafe] Re: Difference between div and /

[Maciej Piechotka]

On Tue, 2010-06-01 at 15:29 -0700, Evan Laforge wrote:
> > [1] By co I mean Ruby, Python, Perl and others. There are no so many
> > languages that do recognize the difference.
> 
> % python -Q new
> Python 2.4.6 (#1, Aug  3 2009, 17:05:16)
> [GCC 4.0.1 (Apple Inc. build 5490)] on darwin
> Type "help", "copyright", "credits" or "license" for more information.
> 10 / 3
> #-> 3.3333333333333335
> 10 // 3
> #-> 3
> 
> 
> The python guys decided that int/int -> int was a mistake, but because
> it's an incompatible change, the removal process has been long (hence
> the -Q flag, or a from __future__ import).  In fact, I think they gave
> up on making it the default before python 3.
> 
> I appreciate that haskell has differentiated from the beginning.

Well - i tried to write some package dealing with distributions etc. 

If you have something like that:

instance ... => Distribution (Linear a) a where
    rand (Linear f s) g =
        let (gf, gt) = genRange g
            (v, g') = next g
        in (g', f + (fromIntegral v * s) / fromIntegral (gt - gf))

(I haven't check it but IMHO it is right implementation)

Now I have following options:

 - Implement per Int/Int8/...
 - Implement IntegerLinear and FractionalLinear separatly

Neither of choices are IMHO not ideal.

Regards
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