[Haskell-cafe] Seeking feedback for a tutorial paper draft about GADTs

Hi Haskellers, I have written a draft of an introductory-level tutorial paper about GADTs in Haskell (for submittion to proceedings of the recent LASER summer school) and I would like to seek initial feedback about its content: what information is probably missing? are there any subtle mistakes? The main idea of this article was to serve as a starting point for learning GADTs (I was missing this kind of information myself some time ago), so I have collected several examples demonstrating common use cases. -- Best Regards, Anton Dergunov