Don Stewart schrieb: > alexey.skladnoy: >> Hello >> >> I found that there is no monadic map for vector. It's possible to define to >> define such map using conversion to list, but I suppose it's not efficient. >> I >> didn't make any measurements. >> >>> mapM' :: Monad m => (a -> m b) -> V.Vector a -> m (V.Vector b) >>> mapM' f = return . V.fromList <=< mapM f . V.toList >> Any suggestions about implementation of such function? >> Specifically I want to use Random monad. >> > > > There's a tutorial here on usving vectors, > > > http://haskell.org/haskellwiki/Numeric_Haskell:_A_Vector_Tutorial#Random_numbers > > mapM is available via Fusion.Stream.Monadic.mapM
But can it be efficient? It must handle cases like m = [] and thus creation of the (V.Vector b) result means a lot of copying, right? _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
