Adrian Hey writes: > The problem is simple enough to restate for anyone who's interested. > "Provide a simple reliable mechanism to ensure that in a given > program run one particular top level IO operation cannot be executed > more than once." > > > Can you give one concrete example of an "intended application > > of oneShot", so that we can either propose a concrete Haskell > > implementation of it, or agree that global variables really are necessary. > > Any C library which requires an explicit initialisation call before anything > in that library can be used (common enough IME). Accidental re-initialisation > (e.g. by two independent modules/libraries) will destroy any state currently > be used by the libraries existing "clients".
Great, thanks, that's just what I was hoping for - I now see the problem you're trying to address. --KW 8-) _______________________________________________ Haskell-Cafe mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell-cafe
