Marcin 'Qrczak' Kowalczyk
20 Mar 2001 17:42:09 GMT
Tue, 20 Mar 2001 18:07:25 +0100 (CET), Andreas Gruenbacher <[email protected]> pisze:
> The sort of lazy evaluation employed in your solution is in a way similar
> to coroutines, with the following restrictions (correct me if I'm wrong):
> * It is not possible to implement cyclic communication.
I see no problem in this.
In fact laziness is really about the ability to cycle anything.
> * It is not possible to implement processes with multiple asynchronous
> output channels.
Again I see no problem:
splitEvenOdd:: [a] -> ([a], [a])
splitEvenOdd  = (, )
splitEvenOdd (x:xs) = (x:ys, zs) where (ys, zs) = splitOddEven xs
splitOddEven:: [a] -> ([a], [a])
splitOddEven  = (, )
splitOddEven (x:xs) = (ys, x:zs) where (ys, zs) = splitEvenOdd xs
What it cannot do is to multiplex input. Code is purely functional
and thus the result cannot depend on the order in which inputs become
Concurrent Haskell provides nondeterministic merge from lazy lists
(mergeIO and nmergeIO in module Concurrent).
__("< Marcin Kowalczyk * [email protected] http://qrczak.ids.net.pl/
^^ SYGNATURA ZASTĘPCZA