Looking for the “Derive through newtype” proposal

Looking for the “Derive through newtype” proposal

I remember reading a GHC proposal for letting users derive instances by wrapping the type in a newtype. It would go something like this:

newtype Apply f a = Apply f a instance (Applicative f, Monoid a) => Monoid (Apply f a) ... data Foo a = ... deriving Monoid through Apply instance Applicative Foo ... 

I think that Icelandjack had made this proposal, but I cannot find it anywhere on the GHC proposals github. Does anyone know where this is?

Submitted August 10, 2017 at 09:51PM by andrewthad
via reddit http://ift.tt/2wxzZ0j


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