Proposal for template-haskell: Make Q an instance of Applicative

[Michael Snoyman]

On Fri, Jul 8, 2011 at 12:56 PM, Bas van Dijk <v.dijk.bas at gmail.com> wrote:
> Hello,
>
> The Q type:
>
> newtype Q a = Q { unQ :: forall m. Quasi m => m a }
>
> currently has an instance for Monad and Functor. I would like to
> propose adding an instance for Applicative as well. Note that this
> also means that the Quasi class needs to get an Applicative
> superclass:
>
> class (Monad m, Applicative m, Functor m) => Quasi m where ...
>
> Discussion period: 2 weeks.
>
> Regards,
>
> Bas
>
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>

+1. But wouldn't it be possible to do this without the Applicative
superclass, using the Monad instance? Not saying we *should* do that,
I'm in favor of your proposal exactly as-is.

Michael