From: Heinrich Apfelmus Don Stewart wrote:

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jmillikin:

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Here's the fastest Haskell version I could come up with. It discards all error handling, validation, and correctness in the name of performance, but still can't get anywhere near C: http://hpaste.org/fastcgi/hpaste.fcgi/view?id=16423

Thanks for posting the code.

You're not using bytestrings??

They were invented to deal with the problem of [Char] being a poor structure for large scale string processing, and you should have no problem getting C-like string performance.

    http://www.cse.unsw.edu.au/~dons/papers/CSL06.html

In my limited experience, ByteStrings are great for reading data, but not that good for writing data that is being generated on the fly. For writing, good old difference lists or the  Builder  monoid / Put monad from Data.Binary seem to be best.

If find that this is particularly true if you don't know the length of data to write in advance because it involves lots of new allocations and copying. Using Builder/Put is definitely a better approach. Out of curiousity, has anyone ever tried implementing a LinkedListString in C to check what its performance would be? I expect it would be pretty poor compared to standard strings. Cheers, John