Re: Efficent lens operation for Data.Map et al.

18 Jan 2012

      On Wed, 18 Jan 2012, Johan Tibell wrote:
...
On Wed, Jan 18, 2012 at 1:51 PM, Roman Cheplyaka  wrote:
...
* roconnor@theorem.ca  [2012-01-18 16:35:52-0500]
...
On Wed, 18 Jan 2012, Johan Tibell wrote:
...
IIRC you just replace the current functions with yours and run make in
the benchmarks/ directory to compile the benchmark binaries (which use
Criterion). Then simply run them.
I got an error trying to build the benchmarks:
Worked for me with GHC 7.0.4.
The results are attached.
In short, your version is indeed typically slower, up to a factor of 5
(for lookup).
That's even slower than I expected. Doesn't mean that we cannot add
the operation though (although we should think about exactly which
operation(s) we need.)
Ya, all I really want is one function:

lens :: Key -> IntMap a -> (Maybe a -> IntMap a, Maybe a)

for every container type.

-- 
Russell O'Connor                                      http://r6.ca/
``All talk about `theft,''' the general counsel of the American Graphophone
Company wrote, ``is the merest claptrap, for there exists no property in
ideas musical, literary or artistic, except as defined by statute.''

Re: Efficent lens operation for Data.Map et al.

roconnor＠theorem.ca