#10188: prefix type-level cons can't be parsed -------------------------------------+------------------------------------- Reporter: Kinokkory | Owner: Kinokkory Type: bug | Status: patch Priority: normal | Milestone: 7.12.1 Component: Compiler | Version: 7.8.4 (Parser) | Keywords: Resolution: | Architecture: Operating System: Unknown/Multiple | Unknown/Multiple Type of failure: GHC rejects | Test Case: valid program | Blocking: Blocked By: | Differential Revisions: Phab:D768 Related Tickets: #10189 | -------------------------------------+------------------------------------- Comment (by goldfire): Looking more closely at this, I think this was not a bug in the parser, but in the pretty-printer. The pretty-printer prints type-level `:::` as `(':::)`, but it should be `'(:::)`, which is what is parsed. Normal type- level cons is parsed the same way, with the tick outside the parentheses. (Which I think is confusing, but that ship has sailed.) On the other hand, it does seem draconian to '''require''' the tick for cons, when `:` has no possible other interpretation as a type-level constant. So, considering this as a feature request, I think it's a good one. Thanks for the patch! Did you end up submitting a separate bug report for the pretty-printer? That's still outstanding, I believe. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10188#comment:10 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler