Inverse of Forget

[robrix]

optics uses Forget for view and Tagged (the flip of Const, if anyone is curious) for review, but one can also define review using a profunctor that’s more clearly related to Forget:

newtype Forget r a b = Forget { runForget :: a -> r }
newtype Recall s a b = Recall { runRecall :: s -> b }

I have defined such a creature for reasons, and, happily, it admits instances of (at least) Costrong, Choice, Closed, Cosieve and Sieve, but only Corepresentable; and at a lower rank, Distributive, Representable, and so on.

If there’d be any interest in it living here I will be happy to submit a PR.