[Haskell-cafe] ANNOUNCE: StrictBench 0.1 - Benchmarking code through strict evaluation

[Magnus Therning]

On Mon, Jun 8, 2009 at 1:56 PM, Martijn van
Steenbergen<martijn at van.steenbergen.nl> wrote:
> Magnus Therning wrote:
>>
>> Is there no way to force repeated evaluation of a pure value?  (It'd
>> be nice to be able to perform time measurements on pure code so that
>> it's possible to compare Haskell implementations of algorithms to
>> implementations in other languages, without running into confounding
>> factors.)
>
> I'm really curious about this too.
>
> My guess is that the answer is "no" because doing so would (among other
> things) mean a thunk have to be copied first before it is evaluated, to
> preserve the unevaluated version. And what guarantee is there that values
> further down the expression haven't been evaluated already? Efficient lazy
> evaluation is hard; inefficient lazy evalation is even harder. ;-)

Yes, I guessed as much.  I was hoping that there might be some way of
tricking GHC into being more inefficient though, something like a
rollback in evaluation state.

/M

-- 
Magnus Therning                        (OpenPGP: 0xAB4DFBA4)
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