Re: [Haskell-cafe] some newbie FFI questions

If you are using GHC the fastest way I know to do this is to build the array using a mutable-unboxed array in the state-monad. Then freeze the array and return an unboxed immutable array. This is a lot faster than building the array by copying (every time you set a value in an immutable array the whole array much be copied - for a sizeable image this is quite a lot of work!) Keean.