I understand that due to the limitations of typed template Haskell, we can't really hope to implement a proper genericTraverse. Unfortunately, I can't currently see an obvious approach to writing one with these generics even if those limitations are overcome. Imagine we try to implement something like
gtr :: (Generic1 t, GTrav (Rep1 t), Quote q) => Code q (Dict (Applicative f)) -> Code q (a -> f b) -> Code q (t a) -> Code q (f (t b))
How would we go about it? Once we apply from1 to the Code q (t a) argument, we find we need
_ :: Rep1 t (Code q) a -> Code q (f (t b))
How can we find a place to use to1 to make code for constructing the result containers?
I understand that due to the limitations of typed template Haskell, we can't really hope to implement a proper
genericTraverse. Unfortunately, I can't currently see an obvious approach to writing one with these generics even if those limitations are overcome. Imagine we try to implement something likeHow would we go about it? Once we apply
from1to theCode q (t a)argument, we find we needHow can we find a place to use
to1to make code for constructing the result containers?