[Haskell-cafe] State monad is missing Applicative instance

Peter Verswyvelen bugfact at gmail.com
Sun Mar 15 09:33:20 EDT 2009

ouch, I was confusing the mtl and transformers package...
so basically transformers is a better replacement for mtl?

or does mtl offer things transformers does not?

On Sun, Mar 15, 2009 at 12:04 AM, Henning Thielemann <
lemming at henning-thielemann.de> wrote:

> On Sat, 14 Mar 2009, Peter Verswyvelen wrote:
>  I was using the transformers but still had to implement the Applicative
>> instance of State
>> This package contains an applicative instance for StateT but not for State
> In 'transformers' State is a type synonym for StateT Identity and thus does
> not need an own instance declaration.
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