Efficent lens operation for Data.Map et al.

[Johan Tibell]

On Wed, Jan 18, 2012 at 1:51 PM, Roman Cheplyaka <roma at ro-che.info> wrote:
> * roconnor at theorem.ca <roconnor at 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.)

-- Johan