[Haskell-cafe] State monad is missing Applicative instance

Henning Thielemann lemming at henning-thielemann.de
Sat Mar 14 19:04:30 EDT 2009

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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