#8827: Inferring Safe mode with GeneralizedNewtypeDeriving is wrong -------------------------------------+------------------------------------ Reporter: goldfire | Owner: Type: bug | Status: new Priority: normal | Milestone: 7.8.1 Component: Compiler | Version: 7.8.1-rc2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: 8226, 8745 -------------------------------------+------------------------------------ Comment (by goldfire): I'll admit to liking the general flavor of comment:27, but the details elude me somewhat. What, precisely, would go after the word `deriving`? What's the interaction between derived instances and role annotations? Could a derived instance be more restrictive than the assigned roles? (It certainly couldn't be ''less'' restrictive!) How would a user specify that? On a separate note, and with no intention to start a flame war, this process would have been easier if we had had a more accurate timeline on the 7.8 release. When some of this debate started in October, we debated under the "late hour" premise, as well. The RCs hadn't gone out, obviously, but any less-than-almost-fully-baked idea was discarded as "too much work too late". If we had known that we had a few months to work out a proposal and implement it, it's possible that we'd be in a better place today. Of course, schedules slip, but communicating a best guess (even as that guess changes) would have been helpful. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8827#comment:29 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler