[Haskell-cafe] Re: Left fold enumerator - a real pearl overlooked?

Manlio Perillo manlio_perillo at libero.it
Mon Mar 2 06:00:50 EST 2009


Eugene Kirpichov ha scritto:
> OK, I'm far from being a supergeek, but anyways.
> 
> I'm not considering the lazy IO approach, as it doesn't involve any
> form of control over resources.

This is not always true.
I'm using lazy IO, still having full control over the resources.

parse path = withFile path ReadMode parse'
     where
       parse' :: Handle -> IO (UArr Xxx)
       parse' handle = do
         contents <- L.hGetContents handle
         let v = toU $ xxx $ L.lines contents
         rnf v `seq` return v

All the file is consumed, before the result is returned.

 > [...]


Manlio Perillo


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