#10577: Use empty cases where appropriate when deriving instances for empty types -------------------------------------+------------------------------------- Reporter: rwbarton | Owner: (none) Type: bug | Status: patch Priority: normal | Milestone: Component: Compiler | Version: 7.11 Resolution: | Keywords: deriving Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #13117, #7401 | Differential Rev(s): Phab:D4047 Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * status: new => patch * differential: => Phab:D4047 Comment: Phab:D4047 fixes this ticket in the sense that more classes now use `EmptyCase` in derived code for empty data types (namely, `Show`, `Lift`, and `Data`). Note that `Eq` and `Ord` are not among these classes—refer to the [https://github.com/ghc-proposals/ghc- proposals/blob/dbf516088d2839432c9568c3d1f7ae28d46aeb43/proposals/0006 -deriving-empty.rst proposal] which Phab:D4047 implements. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10577#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler