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Distributing Haskell on a cluster

haskell-cafe - Sun, 03/15/2015 - 11:53pm
Hi all, I have posted the following question on stackoverflow, but so far I have not received an answer. I have a piece of code that process files, processFiles :: [FilePath] -> (FilePath -> IO ()) -> IO () This function spawns an async process that execute an IO action. This IO action must be submitted to a cluster through a job scheduling system (e.g Slurm). Because I must use the job scheduling system, it's not possible to use cloudHaskell to distribute the closure. Instead the program writes a new *Main.hs* containing the desired computations, that is copy to the cluster node together with all the modules that main depends on and then it is executed remotely with "runhaskell Main.hs [opts]". Then the async process should ask periodically to the job scheduling system (using *threadDelay*) if the job is done. Is there a way to avoid creating a new Main? Can I serialize the IO action and execute it somehow in the node? Bes
Categories: Offsite Discussion

is build breakage data about the main Haskellplatform projects available?

haskell-cafe - Sun, 03/15/2015 - 6:35pm
Dan Luu recently dug up some build performance data about various open source projects, and found that many such projects have broken builds more than half the time. Unfortunately Luu's data set doesn't include Haskell. Does anyone have the facts on this? (A brief search didn't turn up anything.)
Categories: Offsite Discussion

Proposal: add chunksOf to Data.Sequence

libraries list - Sun, 03/15/2015 - 5:45pm
Data.List.Split.chunksOf n xs breaks up a list xs into chunks of n elements each. The internal "splitMap" function Data.Sequence uses to implement zipWith supports a simple and efficient implementation of chunksOf. All in favor, say "aye". Also, I'm still waiting for a response (any response) to my "cycleN" proposal. David _______________________________________________ Libraries mailing list Libraries< at >
Categories: Offsite Discussion

Generalizing map?

libraries list - Fri, 03/13/2015 - 10:32am
A dozen of functions like concat, foldr, mapM, have been generalized through BBP. Then, why do we leave `map` just for lists? Obviously `map` can be generalized, so map :: Functor f => (a -> b) -> f a -> f b map = fmap The current definition of `map` looks too special to be a special case of mapM (map f = runIdentity . mapM (Identity . f)). _______________________________________________ Libraries mailing list Libraries< at >
Categories: Offsite Discussion

Proposal: Export cycleN from Data.Sequence

libraries list - Wed, 03/11/2015 - 4:14pm
Yesterday I rewrote `*>` for Data.Sequence (again), using an internal function cycleN :: Int -> Seq a -> Seq a The name of the function is based on that of Data.Sequence.iterateN. cycleN takes a sequence and cycles it as many times as requested: cycleN 0 $ fromList [1,2] = [] cycleN 5 $ fromList [1,2] = [1,2,1,2,1,2,1,2,1,2] The function is written to maximize sharing in the result sequence and to minimize construction time. Specifically, cycleN n xs should take something like O(|xs| + log n) space (of which all but O(log |xs| + log n) is shared with the structure of xs) and O(log |xs| + log n) time. With current (on GitHub) Data.Sequence exports, the only way to get this functionality with these time and space bounds is to combine replicate with *> : cycleN n xs = replicate n () *> xs This strikes me as a bit unpleasant. David
Categories: Offsite Discussion

-staticlib flag for building standalone static libraries producing very large libraries

glasgow-user - Sat, 03/07/2015 - 1:18pm
Hi all, Can anyone explain the following problem I'm having? I'm currently writing a game in Haskell. When I produce a plain old executable (for local testing) it's about 23M. However, when I create a static lib using the -staticlib flag it is 54M. Why the discrepancy? Sean _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users< at >
Categories: Offsite Discussion

New gtk2hs 0.12.4 release

gtk2hs - Wed, 11/21/2012 - 12:56pm

Thanks to John Lato and Duncan Coutts for the latest bugfix release! The latest packages should be buildable on GHC 7.6, and the cairo package should behave a bit nicer in ghci on Windows. Thanks to all!


Categories: Incoming News