#8809: Prettier error messages? -------------------------------------+------------------------------------- Reporter: joelteon | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.9 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: 13122 Related Tickets: | Differential Rev(s): #8809,#10073,#10179,#12906 | Wiki Page: | -------------------------------------+------------------------------------- Comment (by mpickering): Here is how I see this ticket. There are two suggestions: 1. Make it possible to output error messages as JSON (what I want and easy with current infrastructure). 2. Add more semantic information to error messages (ie attaching the actually expressions to SDocs, what Ben is mainly talking about, idris style). Ben in his last comment is saying that if 2. is implemented then 1. comes for free (I think). The main advantage of 2. is that you can build interfaces which use the additional localised information to provide different information to users, ie highlighting, hovers etc. This seems right to me but implementing 2. is a significant amount of work compared to 1. and I can't imagine the exact design off the top of my head. My essential point is that 1. should not be blocked by 2. Once 2. is implemented then 1. can be reimplemented in terms of 2. There seems to be suggestions of how to resolve the `pretty` issue but even after that there is still an extremely large amount of work to embed the right information in the SDoc. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8809#comment:59 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler