[Haskell-cafe] primitive operations in StateT
cgaebel at uwaterloo.ca
Tue Apr 16 08:08:06 CEST 2013
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!
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 <cgaebel at uwaterloo.ca> 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
>> > 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 at haskell.org
>> > http://www.haskell.org/mailman/listinfo/haskell-cafe
>> Ivan Lazar Miljenovic
>> Ivan.Miljenovic at gmail.com
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