[Haskell-cafe] Applicative Monoid instance

[Tom Ellis]

On Mon, Sep 05, 2016 at 02:54:20PM -0400, Brian Hurt wrote:
> This may be a stupid question, but I'm wondering why the following instance
> isn't in prelude:
> 
> instance (Applicative m, Monoid a) => Monoid (m a) where
>     mempty = pure mempty
>     mappend a b = mappend <$> a <*> b
> 
> ?

Is 'liftA2 (<>)' not good enough?