integer-simple by default

Ian Lynagh igloo at
Sun Feb 21 13:14:08 EST 2010

On Sat, Feb 20, 2010 at 02:56:53PM -0500, Isaac Dupree wrote:
> On 02/20/10 14:37, Ian Lynagh wrote:
>> There's also HIntegerByInt:
>> although it would need to be changed to user lower level types etc.
> that's true, (I wrote it), the current form uses a list-based  
> implementation with a lot of recursion and I'd have to see how well that  
> converts to some sort of array [at least I assume arrays are the only  
> reasonable storage layout...].  I used a couple algorithms to make  
> operations faster (at least multiplication -- I don't remember the  
> details) so it might be useful code to pick up again.  I have a bit of  
> time now, if anyone's seriously interested, I could work on haskell  
> integer code.  As long as I had certain standards
> -what am I trying to accomplish (at least, performance-wise)?

I think opinions are divided on this.

Performance with word-sized Integer's is definitely important.

> -what might be a good low-level format? (And is it important to strew  
> unboxed ints all over the place, or is it fine to skip this and count on  
> the optimizer?)

I think relying on the optimiser is OK, but don't forget that you don't
have the standard (+) etc.


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