#2530: deriving Show adds extra parens for constructor with record syntax -------------------------------------+------------------------------------- Reporter: spl | Owner: bgamari Type: bug | Status: new Priority: highest | Milestone: 8.0.1 Component: Compiler | Version: 6.8.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D669 Wiki Page: | -------------------------------------+------------------------------------- Comment (by hvr): Replying to [comment:33 RyanGlScott]:
Well, if people find this objectionable, I suppose we also need to review #10104, since that also resulted in a change in `Show` output.
There's a big difference though: #2530 wants to fix a deliberate deviation (i.e. many people here consider `{}` binding tighter than function application to be a design-flaw) from the Haskell Report. Those additional brackets are harmless and don't harm the expectation of 'Show' resulting in an expression that parses back to the original. On the other hand, #10104 covers an area outside the Haskell Report (`-XMagicHash`) and more importantly fixes the actual problem that `show (MkT 3#)` results in `MkT 3` which can't be parsed back to the original due to a kind-error. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/2530#comment:35 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler