Re: Haskell Platform Proposal: add transformers and revise the mtl package to depend on it

On Thu, Sep 16, 2010 at 11:10:37AM +0200, Johan Tibell wrote:

I would like to know if this additional abstraction has a noticeable performance cost. Does anyone know of a benchmark that could be used to test this? Perhaps one involving State.

With mtl-1, the following incr1 :: State Int () incr1 = do n <- get put $! n+1 incr2 :: StateT Int Identity () incr2 = do n <- get put $! n+1 generate the same Core code (except for casts).