2008/9/3 Bulat Ziganshin <[EMAIL PROTECTED]>: > Hello minh, > > Wednesday, September 3, 2008, 2:09:38 PM, you wrote: > >> I'd like to write a data structure to be used inside the IO monad. >> The structure has some handles of type Maybe (IORef a), >> i.e. IORef are pointers and the Maybe is like null pointers. > > i've not used this but overall it seems like a correct way to emulate > NULL. the whole question is that you probably still think C if you > need NULL pointers at all :)
Maybe, I'm adapting some C++ code... Do you suggest I use data Thing = Thing | None and IORef Thing instead of data Thing = Thing and Maybe (IORef Thing) ? I'm writing a data structure that can hold Things (and that can be mutated) or nothing (there is a hole in the wrapping data). Thanks, Thu _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
