Hello,

my concern is mainly with introducing multiple language constructs that do almost the same thing and neither is better than the other as I think this complicates the language unnecessarily.

Vladislav, I am not sure of the details of your example, but isn't it the case that you could write it with scoped type variables if you wrote the type down? I agree that this can be a pain,

and as far as I see, this is the main use case for this feature---it provides an easier way to call higher-rank functions, when you need to refer to the type parameter in the polymorphic argument.

-Iavor

On Fri, Feb 22, 2019 at 2:48 AM Vladislav Zavialov <vlad.z.4096@gmail.com> wrote:

Dear GHC steering committee,

> In the end, this proposal does not bring in much over ScopedTypeVariables

Please note that comparing this feature to ScopedTypeVariables does
not capture the full picture. There are two examples of code in the
proposal, which I provided, that cannot be expressed using
ScopedTypeVariables without a dummy Proxy argument.

> With finite effort cycles, we may have more important fish to fry.

I was planning to implement this proposal if it would be accepted.

All the best,
- Vladislav