Hello Brian, Saturday, February 04, 2006, 4:50:44 AM, you wrote:
>>> One question is how to get some kind of "do" notation that would >>> work well in a strict setting. >>> The existing "do" notation makes use of lazyness in so far as the >>> second arg of >> is only evaluated when needed. Perhaps a new >>> keyword such as "go" could be used to use >>= instead ie: BH> If strictness was the default (eg if the language were ML not Haskell), then BH> in BH> putStr "hello" >> putStr (show 1) BH> both args to >>> would be evaluated before >> was called. Thus putStr (show BH> 1) would be evaluated before the combined monad is actually run, which would BH> be wasteful if we were using a monad with a >> function that only runs the BH> rhs conditionally on the result of the lhs. BH> If Haskell were a strict language I think an equivalent for the do notation BH> would have to lift everything (except the first expression) and use >>= BH> instead of >>> . it seems that you misunderstand the monads (or may be i misunderstand :) each and every monadic operation is a function! type "IO a" is really "RealWorld -> (RealWorld,a)" and the same for any other monad. concept of the monad by itself means carrying "hidden" state from one monadic operation to the next. that allows to _order_ monadic operations plus this state used for zillions other things, including state, logs, fails and so on, so on -- Best regards, Bulat mailto:[EMAIL PROTECTED] _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
