#13140: Handle subtyping relation for roles in Backpack -------------------------------------+------------------------------------- Reporter: ezyang | Owner: ezyang Type: feature request | Status: patch Priority: normal | Milestone: 8.4.1 Component: Compiler (Type | Version: 8.1 checker) | Keywords: backpack hs- Resolution: | boot Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3123 Wiki Page: | -------------------------------------+------------------------------------- Comment (by goldfire): The Right Thing to do is to go back in time and erase the idea of roles from our brains... and reimplement `GeneralizedNewtypeDeriving` in terms of a generated blob of source code that gets type-checked (instead of the magical implementation it used to have). Barring that, I can't find an argument against a new abstract role other than to harrumph as loudly as I can. Harrumph! -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13140#comment:9 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler