Hi,
The only problem is that it will take some work to adapt haskell-src-exts to Haskell 20nn. I spoke to Niklas about this. He has in principle volunteered to take on the task, but he can't start on it for a few months. And I don't think it would be wise to make the package name changes and end-of-life the current haskell-src until this is done.
Yes, I agree with both Duncan and Yitz here. It would be some monkey work to introduce a "simple" AST, but nothing tricky in principle. I wouldn't mind adding such an AST to haskell-src-exts, and I think that's the best solution long-term.
Niklas has got a lot on his plate without doing this simple AST - I've filed at least 3 bugs against his libraries in the last week! I'm not entirely sure what the intended audience is for this simple AST. Unless someone's going to use it, I don't see much point in it existing. I regularly use haskell-src-exts without caring about lots of extensions, and it just works. Having all the extensions there just means that when I do need them I don't need to switch library/module at all.
So unless someone else can do the work, we may have to wait until the following HP release.
I see no reason to even suggest this work be a precondition for inclusion in the platform. I use HSE more than most people, and I'd consider a simple AST to just be adding bulk. Without a compelling use case it seems you're burning the universes entropy for no good reason :-) Thanks, Neil