Proposal #2316: Add Applicative instances for all MTL Monads

Isaac Dupree isaacdupree at
Thu May 29 06:44:12 EDT 2008

Spencer Janssen wrote:
> This proposal is very straightforward: add Applicative instances for all the
> Monads in the MTL.

It's not quite as straightforward as it looks:
If you only need an
instance (Applicative m) => Applicative (Transformer m),
instance (Monad m) => Applicative (Transformer m),
will you use the first one?  (I think yes.)


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