On Wed, 21 Dec 2005, Peter Simons wrote: > > Some example for writing a text the IO oriented way: > > do putStrLn "bla" > > replicateM 5 (putStrLn "blub") > > putStrLn "end" > > > > whereas the lazy way is > > putStr (unlines (["bla"] ++ replicate 5 "blub" ++ ["end"])) > > Um, maybe it's just me, but I think the first program is far > superior to the second one. The last thing you want your I/O > code to be is lazy. You want the exact opposite: you want it > to be as strict as possible. Not only does the second > version waste a lot of CPU time and memory for pointlessly > constructing a lazily evaluated list nobody ever needs, it > will also explode into your face the moment you use that > approach to write any non-trivial number of bytes. >
Surely the actual explosion comes about because PutStr forces the lot at once? If PutStr were to evaluate a character at a time, the laziness would be slow and spew a lot of garbage to collect but not hang on to as much space as you suggest. Not to say that the strict solution isn't still more efficient, of course. -- [EMAIL PROTECTED] The task of the academic is not to scale great intellectual mountains, but to flatten them. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe