Status of nubOrd (Proposal #2629)

Leon Smith leon.p.smith at
Tue Mar 2 23:23:07 EST 2010

On Mon, Mar 1, 2010 at 2:35 PM, Gwern Branwen <gwern0 at> wrote:
> Hm. But sort was recently modified with some tricks from nhc, IIRC. Is
> it up to date?

data-ordlist is up to date now.  Thanks for the heads up!

I played a bit with implementing the ascending part of the new
implementation using a splitAt-style recursion,  instead of a DiffList
technique.  In some cases it appears to be better,  in others a bit
worse,  and in most cases no substantial changes.      The difference
appears to be mostly related to memory use patterns.

If you sort an already sorted list,  this technique is ~45% faster,
but if you sort a list that consists of long runs of ascending chains,
  it's a bit slower.   I don't know why,  and haven't dug any deeper.

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