[Haskell-cafe] haskell2010 and state question.

Henk-Jan van Tuyl hjgtuyl at chello.nl
Wed Dec 8 11:46:00 CET 2010

On Wed, 08 Dec 2010 10:03:40 +0100, Magicloud Magiclouds  
<magicloud.magiclouds at gmail.com> wrote:

> Hi,
>   Formerly, I had IORef and some state monad to do the task of keeping  
> states.
>   Now in haskell 2010, I cannot find anything about it. Do I have to
> use ghc base package for this function?

These are not standard Haskell '98 or Haskell 2010. You can find IORef in  
the base package; the state monad is in both the mtl and the transformers  
package (mtl is deprecated). The state monad uses the multi-parameter type  
class extension and is therefore not in standard Haskell '98 or Haskell  
2010 code. IORef also uses non-standard code.

Henk-Jan van Tuyl


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