[Haskell-cafe] Comments and suggestions on code

Andre Nathan andre at digirati.com.br
Fri Jan 11 10:27:33 EST 2008

On Thu, 2008-01-10 at 20:37 -0800, Jonathan Cast wrote:
> It might be faster; laziness usually has higher constants than direct  
> implementations.  But I doubt the difference is critical in this  
> case, and I would definitely time a re-writing and throw it away  
> unless it was significantly faster.  But I don't think this is a case  
> where laziness actually alters either the time or the space  
> asymptotics of the algorithm (you end up creating an ~ O(n) tree  
> anyway, so I'd figure O(n) space was OK for the loop, too).

I was wondering if laziness would make it run as if it was a single O(n)
operation (get one directory entry "on demand", pass it to filter and
then to insertInTree), because only one entry is used at a time, so that
only the "current" entry needs to be evaluated.

I still find it hard to evaluate the effects of laziness on the
complexity of programs...


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