#12605: UnboxedSums causes parse error on hash operator e.g. `let (#) = (+)` -------------------------------------+------------------------------------- Reporter: jberryman | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by jberryman): Oh I see you're right, and maybe this is a dup of https://ghc.haskell.org/trac/ghc/ticket/12459 However even if that's expected under `UnboxedTuples`, this seems to be a worse situation under `UnboxedSums`. I'm looking at https://ghc.haskell.org/trac/ghc/wiki/UnpackedSumTypes under "Unpacking ... This part is not yet implemented..." it seems to me the intention is to allow `UnboxedSums` to automatically optimize (has this been implemented in HEAD yet btw?): {{{ data T1 a = Some a | None data T2 a = C {-# UNPACK #-} !(T1 a) }}} So a user might like to enable on a source tree for purposes of optimization; they don't need or want access to any new syntax. Let me know if I should open any new tickets. Feel free to do whatever you think with this one. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12605#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler