2533: Generic functions that take integral arguments should work the same way as their prelude counterparts

Henning Thielemann lemming at henning-thielemann.de
Fri Aug 22 11:49:22 EDT 2008


On Fri, 22 Aug 2008, Neil Mitchell wrote:

> Hi
>
>> The Prelude functions drop, take, and splitAt are unfailing (never
>> call error). This patch changes the Data.List generic versions to
>> behave the same way. At present, they call error on negative
>> arguments.
>
> I had always just assumed that take and genericTake did the same
> thing, so had never even realised this problem existed. I'd call this
> a bug, that needs fixing.

Maybe the bug is in 'drop', 'take' and 'splitAt' and it was intended to 
fix it in 'generic' variants. Is there a good reason why to ignore 
negative number arguments? It may hide bugs.


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