Am Mittwoch, 15. April 2009 09:03 schrieb Achim Schneider:
I don't think using dirty tricks to implement FRP deserves flak, at all, from my POV, it sounds like complaining that the IO monad is implemented using C... meaning that if you're that close to bare thunks, you have every right to use any means necessary to make them behave properly.
It depends. Using unsafe stuff internally, might be acceptable and sometimes necessary. I also use unsafePerformIO in Grapefruit for implementing CSignals although I’m not very comfortable with this. On the other hand, breaking referential transparency in the external interface is a very bad idea, in my opinion. Actually, this means that the library user would have to turn certain compiler optimizations off to get the intended behavior. Just have a look at the Haddock docs of unsafePerformIO. In my earlier years of Haskell programming, I thought that unsafePerformIO is not too bad but I had to discover that it can quickly lead to a catastrophe. Best wishes, Wolfgang