I'm testing iteratee. This is the possible bug I've found import Data.Iteratee.IO import Data.Iteratee.Base import Data.Iteratee.Char import System.IO import Control.Exception main = do h <- openFile "mamma23" ReadWriteMode hPutStrLn h "ciao" hSeek h AbsoluteSeek 0 l <- (enumHandle h stream2list :: IO (Iteratee IO String)) >>= run print $ assert (l == "ciao") () assertion failed This aside, I'd like to know if there is a way to use parsec library to make an Iteratee, so if it's possible to make parsec spit out a continuation on EOF, or maybe as in delcont language to capture it. thanks paolino
Hi Paolino. What's happening is reading [Char] uses the Storable instance for Char which is 32-bit. Thus, you get gibberish. The below does what you want, by reading Word8s and converting them. import Control.Exception import Data.Char import Data.Iteratee.IO import Data.Iteratee.Base import Data.Word import System.IO main :: IO () main = do h <- openFile "mamma23" ReadWriteMode hPutStr h "ciao" hSeek h AbsoluteSeek 0 l <- enumHandle h readString >>= run print $ assert (l == "ciao") () -- This is declared on its own so I can give a type signature without making -- any of the above lines unmanageably long. readString :: IterateeG [] Word8 IO String readString = joinI $ mapStream (chr . fromIntegral) stream2list This only works for ASCII, of course. Someone should write some enumerators for the other encodings. Regards, Echo Nolan
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