Re: [Haskell-cafe] primitive operations in StateT

*sigh* nevermind. I found it. Turns out there was: liftMCT :: (Monad m) => MC a -> MCT m a in an unexported module in the monte-carlo package all along. I just need to export it and I'll be good to go. Thanks for your help! - Clark On Tuesday, April 16, 2013, Clark Gaebel wrote:

The monad my code is currently written in is:

type MC = MCT Identity -- where MCT is the monad transformer version of it.

I have two options for threading state through this:

MCT (ST s) a StateT s MC a

The first option would work if I had some function with the signature

MCT Identity a -> MCT (ST s) a

but I know of no such function, and the second one would work if I had some way of making StateT a member of PrimMonad.

Can I see an example with 'lift'?

- Clark

On Tuesday, April 16, 2013, Ivan Lazar Miljenovic wrote:

...

On 16 April 2013 15:04, Clark Gaebel wrote:

...

Hi list!

I want to use MVectors in a StateT monad transformer.

How do I do that? StateT isn't a member of 'PrimMonad', and I have no idea how to make it one.

You can use Control.Monad.Trans.lift to lift the PrimMonad operations to PrimMonad m => StateT s m

...

Regards, - Clark

_______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

-- Ivan Lazar Miljenovic Ivan.Miljenovic@gmail.com http://IvanMiljenovic.wordpress.com