#12550: Inconsistent unicode display for kinds ---------------------------------+-------------------------------------- Reporter: johnleo | Owner: johnleo Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Operating System: MacOS X | Architecture: x86_64 (amd64) Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | ---------------------------------+-------------------------------------- Comment (by johnleo): Ben's fix for #11660 handled almost all of the problems. The sole remaining problem was the result of conflation between the input format of kind * (`*`, `★` or `Type`), the internal representation, and the output format. If * was inferred it was output correctly, but if it was explicitly specified in the type signature it would be output in that form, which means the output format could be a confusing mixture of `*`, `★` and `Type`. I have unified the output format to be `*` when non- unicode output is expected and `★` when `-fprint-unicode-syntax` is enabled. Note that in the future we may output `Type` in all cases instead (see #12030) but this will not happen for some time; I plan to create a proposal for this. I wanted to go further and unify the internal representations of `*`, `★` and `Type` by setting the key of all three to be `liftedTypeKindTyConKey` since internally they are all fundamentally the same thing. However this caused a panic in `PrelInfo.knownKeyNamesOkay` since apparently all keys have to be unique. I wonder if that condition could be relaxed. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12550#comment:9 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler