Re: [Haskell-cafe] ST not strict enough?

On 18 November 2011 13:17, Daniel Fischer wrote:

On Friday 18 November 2011, 13:05:06, Yves Parès wrote:

...

...so there is no way to do that inside the function passed to modifySTRef? In other words, there is no way to ensure inside a function that its result will be evaluated strictly?

Well,

modifySTRef ref fun = do    val <- readSTRef ref    writeSTRef ref  (fun val)

But note therefore that you can just: val <- readSTRef ref writeSTRef ref $! fun val rather than using modifySTRef. Duncan