Re: [Haskell-beginners] Global variables

Although it is generally considered an anti-pattern, it is possible to implement a true mutable, global counter [1] a la every-other-imperative-language in Haskell. As some other people have indicated you're better off with the State monad, but this style comes in handy when you need to translate imperative code into Haskell without having to do a complete redesign. -deech [1] http://stackoverflow.com/questions/6302249/how-to-implement-a-global-counter... On Wed, Jun 29, 2011 at 10:47 AM, Michael Xavier wrote:

I think my head isn't on straight this morning. I think I meant something more along the lines of Control.Monad.State

On Wed, Jun 29, 2011 at 8:27 AM, Christopher Done wrote:

...

On 29 June 2011 17:22, Michael Xavier wrote:

...

I tend to use Control.Monad.Reader for stateful stuff like this. It is found in the mtl package http://hackage.haskell.org/package/mtl-2.0.1.0

How would you use reader for a counter?

-- Michael Xavier http://www.michaelxavier.net

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