#9788: `coerce` has an impossible type -------------------------------------+------------------------------------- Reporter: goldfire | Owner: goldfire Type: bug | Status: patch Priority: highest | Milestone: 7.10.1 Component: Compiler | Version: 7.8.3 Resolution: | Keywords: Operating System: | Architecture: Unknown/Multiple Unknown/Multiple | Difficulty: Easy (less than 1 Type of failure: | hour) None/Unknown | Blocked By: Test Case: | Related Tickets: Blocking: | Differential Revisions: Phab:D468 | -------------------------------------+------------------------------------- Comment (by nomeata): It was commit 2f3ea95285d0cccc2a999e7572d8fb78dc2ea441 that made this type signature issue visible. Note that you even updated the users guide with this particular example, so I guess you’ll need to find one that is not horribly wrong :-). The original cause was 976a1087ae75accb4ad9d869d14641b2581c1606 implementing #8541. I back then just assumed that if `Coercible` has to be higher-kinded, then `coerce` has to be too. I guess I was wrong... -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9788#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler