[GHC] #14893: GHC hangs while producing error message for incorrect TypeFamilies application

[GHC]

#14893: GHC hangs while producing error message for incorrect TypeFamilies
application
-------------------------------------+-------------------------------------
        Reporter:  coopercm          |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:  duplicate         |             Keywords:
Operating System:  Linux             |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #12386            |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by RyanGlScott):

 * status:  new => closed
 * resolution:   => duplicate
 * related:   => #12386


Comment:

 Thanks for the bug report. I believe this is in fact a duplicate of
 #12386, as this gives a proper error on GHC 8.4.1:

 {{{
 $ /opt/ghc/8.4.1/bin/ghci Bug.hs
 GHCi, version 8.4.0.20180224: http://www.haskell.org/ghc/  :? for help
 Loaded GHCi configuration from /home/rgscott/.ghci
 [1 of 1] Compiling Main             ( Bug.hs, interpreted )

 Bug.hs:11:27: error:
     • Expecting two more arguments to ‘Meta’
       Expected a type, but ‘Meta’ has kind ‘* -> (* -> *) -> *’
     • In the second argument of ‘Token’, namely ‘Meta’
       In the type ‘Token f Meta’
       In the default type instance declaration for ‘Body’
    |
 11 |   type Body x f = Token f Meta
    |                           ^^^^
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14893#comment:1>
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