#8868: Old information in Extensions to data types and type synonyms --------------------------------------+------------------------------------ Reporter: Kinokkory | Owner: Type: bug | Status: new Priority: normal | Milestone: ⊥ Component: Documentation | Version: 7.6.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: Documentation bug | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: --------------------------------------+------------------------------------ Changes (by Kinokkory): * version: 7.8.1-rc2 => 7.6.1 * milestone: 7.8.1 => ⊥ Comment: I just would like to make the User's Guide faithful to the behavior of the GHC 7.6.*. I'm not talking about the behavior of the release candidate. (I believe ''symbol infix type variables'' should be legal, but I'm not sure.) The problem is whether the GHC accepts this code. {{{ type T (+) = Int + Int f :: T Either f = Left 3 liftA2 :: Arrow (~>) => (a -> b -> c) -> (e ~> a) -> (e ~> b) -> (e ~> c) liftA2 = ... }}} The User's Guide of GHC 7.8.1-rc1 says http://www.haskell.org/ghc/docs/7.8.1-rc1/html/users_guide/data-type- extensions.html#type-operators In types, an operator symbol like (+) is normally treated as a type variable, just like a. ... As you can see, using operators in this way is not very useful, and Haskell 98 does not even allow you to write them infix. So it seems that the new version's documentation have reflected the change. If GHC isn't willing to change the documentations of released versions, close this ticket. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8868#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler