Re: [Ocaml-lib-devel] Idea with ExtList.fold_right

[John M. S. <sk...@oz...>]

Brian Hurt wrote:

> On Sat, 14 Jun 2003, John Max Skaller wrote:
> 
> 
>>i don't want you counting my lists :-)
>>
> 
> What is so evil about doing a List.length?  Especially in this case, where 
> I hard cap the computational cost- as all I need to answer is if the 
> length less than some constant.  So, for short lists (for some suitably 
> wimbly definition of short) doing a list length is cheap.  

Nothing is cheap inside an inner loop :-)
The count could cost as much as a fold,

particularly as a count IS in fact a fold.


So you might double my computation time,

if I have a heavily nested fold on a small list.
I may even know the list is always small,
and hope the compiler may speed things up by
unrolling the fold :-)

-- 
John Max Skaller, mailto:sk...@oz...
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