On Sun, 7 Sep 2008, Brandon S. Allbery KF8NH wrote:
You seem to think we must never insure that something will only be run once, that any program that does require this is broken. As such, the standard Haskell libraries (including some whose interfaces are H98) are unfixably broken and you'd better start looking elsewhere for your "correct behavior".
Data.Unique might be unfixably broken, though perhaps some requirement that it not be unloaded while any values of type Unique are still around could solve the problem - though it's hard to see how this could be implemented sanely. But Data.Unique could (a) probably be replaced with something in terms of IORefs and (b) is pretty ugly anyway, since it forces you into IO.
I'm sure that for many other examples, re-initialisation would be fine. For example Data.HashTable just uses a global for instrumentation for performance tuning, which could happily be reset if it got unloaded and then reloaded. System.Random could get a new StdGen. I haven't yet had time to go through the entire list that Adrian Hey posted to understand why they are being used, though.
I'd also point out that if you unload and load libraries in C, global state will be lost and re-initialised.
Ganesh _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
