On Wed, Mar 14, 2012 at 5:50 PM, wren ng thornton <w...@freegeek.org> wrote: > Do note, however, that in certain cases the ST approach can be much slower > than the obvious immutable approach (i.e., the State monad--- especially > when implemented directly via argument passing, rather than using the > monadic interface). I have some closed-source code where that assumption bit > me; the ST code was over 4x slower.
An additional reason is that runST often allocates a closure (as it's marked NOINLINE) and thus using it e.g. in a tight loop can increase allocation. -- Johan _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
