[Haskell-cafe] Bug in writeArray?

Iavor Diatchki iavor.diatchki at gmail.com
Thu Sep 24 12:32:13 EDT 2009


I agree with Grzegorz.  Perhaps we should file a bug-report, if there
isn't one already?
-Iavor

2009/9/24 Grzegorz Chrupała <pitekus at gmail.com>:
> 2009/9/23 Bulat Ziganshin <bulat.ziganshin at gmail.com>:
>> Hello Grzegorz,
>>
>> Wednesday, September 23, 2009, 7:19:59 PM, you wrote:
>>
>>> This seems like a bug in the implementation of writeArray: when passed
>>>   let (l,u) = ((0,10),(20,20))
>>
>> writeArray computes raw index (from 0 to total number of array
>> elements) and check that this index is correct. with multi-dimensional
>> arrays this approach may lead to wrong results, as you mentioned. it's
>> known problem that isn't fixed for a long time probably due to
>> efficiency cautions.
>
> Hmm, I understand that efficiency is an issue, but in that case
> shouldn't unsafe writing be provided by and unsafeWriteArray function,
> while writeArray does proper range checking?
>
> Or at least this problem with writeArray should be clearly indicated
> in the documentation. I for one spent several hours debugging before
> finding out about this lack of proper range checks so it's not an
> imaginary problem.
>
> --
> Grzegorz
> _______________________________________________
> Haskell-Cafe mailing list
> Haskell-Cafe at haskell.org
> http://www.haskell.org/mailman/listinfo/haskell-cafe
>


More information about the Haskell-Cafe mailing list