Data.HashTable
Neil Mitchell
ndmitchell at gmail.com
Thu Mar 6 16:48:53 EST 2008
Hi
> I learned at school, and I teach my students,
> * balanced binary tree: costs are log(size)
> * hashtable: cost are essentially constant
All true, but log(1000) = 10 [nitpick, its nearly always log base 2,
not base 10]. 10 ~= constant.
> ... but indeed some experiments with Data.Map and Data.Hashtable
> support the point you made. That's either good for Data.Map
> or bad for Data.Hashtable.
I think both of those are true. Hashtable isn't a natural functional
data structure, so is ignored, so is not improved. I suspect a Trie
would be a much better data structure for most of the uses of
Hashtable, but alas there is not one in the standard libraries.
Thanks
Neil
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