[Haskell-cafe] state monad transformer that adds or combines state

[Vanessa McHale]

You can apply StateT to an existing monad, e.g. StateT StateType (Either
ErrorType). Then 'get' and 'put' can be used inside this monad.


On 05/15/2018 04:29 PM, Dennis Raddle wrote:
> I'm not sure what happens if I apply a StateT to an existing State or
> StateT monad. Not sure how 'get' and 'put' would function, or if I
> would need to lift get and put to choose which state to access.
>
> D
>
> On Tue, May 15, 2018 at 12:49 AM, Francesco Ariis <fa-ml at ariis.it
> <mailto:fa-ml at ariis.it>> wrote:
>
>     On Mon, May 14, 2018 at 10:27:19PM -0700, Dennis Raddle wrote:
>     > In local computations, I may want to use some additional state.
>     Is there a
>     > way to add a little extra state temporarily?
>
>     Would StateT work (in general, taking advantage of what transformers
>     have to offer)?
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