Hi, I would like to take some time to study Haskell properly, so that I could help others and pay my debt for the many times I had to bother with my syntax questions. And, of course, make better use of the language. My first attempt was to read the syntax description in Haskell 98 report, and that helped a lot. But I've realized that it's far from the language as used today. But just adding all available extensions would not be good, as some are very experimental e others are obsolete. I saw Haskell-prime page and a few features are marked as accepted. That mean I can trust them to be part of the next Haskell standard? So: if someone wants to learn the details of the language, what could be the subset of extensions one should learn and make regular use, and also include in code supposed to be used by others in the long term? Thanks, Maurício