It's not OK and it's an artifact of the weak-typing and ill-defined semantics that pervade iteratee libraries. It's possible to do a lot of bad stuff, including binding with an iteratee yielding a remainder without consuming input.
Regards, John A. De Goes Twitter: @jdegoes LinkedIn: http://linkedin.com/in/jdegoes On Apr 19, 2011, at 6:27 AM, Daniel Schüssler wrote: > Hello, > > for reference, said instance is: > >> instance Monad m => Monad (Iteratee a m) where >> return x = yield x (Chunks []) >> >> m0 >>= f = ($ m0) $ fix $ >> \bind m -> Iteratee $ runIteratee m >>= \r1 -> >> case r1 of >> Continue k -> return (Continue (bind . k)) >> Error err -> return (Error err) >> Yield x (Chunks []) -> runIteratee (f x) >> Yield x extra -> runIteratee (f x) >>= \r2 -> >> case r2 of >> Continue k -> runIteratee (k >> extra) >> Error err -> return (Error err) >> Yield x' _ -> return (Yield x' >> extra) > > The thing I don't understand yet is the last line: Why is it OK to discard > the > leftover input from the (f x) Iteratee and yield just the leftover input from > the first one (m0)? > > Cheers, > Daniel > > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@haskell.org > http://www.haskell.org/mailman/listinfo/haskell-cafe _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
