No, I haven't followed the language in 6 years. I remember there was at least one instance but can't recall. Other extensions significantly change the semantics of language module interfaces in more obtrusive ways than I'd like - compared to say C where it's pretty easy to offer a simple interface.
Some of these things would make working in the language pretty painful. I remember trying some library to toy around with a basic 400 line OpenGL program. It always needed 8 seconds to rebuild at the time. I don't recall and probably didn't understand why, but I suppose it has to do with some extra type or template hackery in the library that would just overcomplicate everything, probably even at the outset.
What remains is the feeling of, I can't do this thing yet in the type system, so take that extension. Oh wow. Now I can't do this other thing that I also need, the only fix is another extension (if it's available yet). I couldn't get around of this feeling of constantly having to hack around the language.
In my experience you need to have a very good overview and understanding of all the available tricks and extensions to be able to navigate your way around the language and not paint yourself into a corner. Maybe I have the wrong personality, the wrong motivations, or am just not smart enough. Obviously I'm not you, and am not Edward Kmett (who would resort to lots of GHC specific hacks and drop down to C++ as well).
> I remember trying some library to toy around with a basic 400 line OpenGL program. It always needed 8 seconds to rebuild at the time.
This is a fair criticism. Compile times are slow.
Extension confusion is not a fair criticism. Extensions typically remove restrictions. They don't create incompatible languages.
Granted, it's a bit annoying to have to turn them all on, one by one. These days one should just enable GHC2021 and forget about language extensions. That saves one having to be Edward Kmett, or from bothering to think about language extensions at all.
Some of these things would make working in the language pretty painful. I remember trying some library to toy around with a basic 400 line OpenGL program. It always needed 8 seconds to rebuild at the time. I don't recall and probably didn't understand why, but I suppose it has to do with some extra type or template hackery in the library that would just overcomplicate everything, probably even at the outset.
What remains is the feeling of, I can't do this thing yet in the type system, so take that extension. Oh wow. Now I can't do this other thing that I also need, the only fix is another extension (if it's available yet). I couldn't get around of this feeling of constantly having to hack around the language.
In my experience you need to have a very good overview and understanding of all the available tricks and extensions to be able to navigate your way around the language and not paint yourself into a corner. Maybe I have the wrong personality, the wrong motivations, or am just not smart enough. Obviously I'm not you, and am not Edward Kmett (who would resort to lots of GHC specific hacks and drop down to C++ as well).