Re: [GHC] #15400: Parse error on input ‘*’

[GHC]

#15400: Parse error on input ‘*’
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        Reporter:  Bodigrim          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #15284            |  Differential Rev(s):  Phab:D4865
       Wiki Page:                    |
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Comment (by goldfire):

 Oh dear. I've gotten confused about this again! And then I went ahead and
 confused Ben. I really should know better.

 This is expected behavior. In GHC 8.6, you have to specify
 `-XNoStarIsType` in order to use `*` as a type operator. We recognize that
 this makes for an awkward migration for some users, but, as discussed in
 [https://github.com/ghc-proposals/ghc-proposals/pull/83 these]
 [https://github.com/ghc-proposals/ghc-proposals/pull/146 proposals] (more
 the second one), it seemed better to do it this way than any other we
 could think of.

 Just put on `-XNoStarIsType` and you'll be off.

 However, do we have any migration guide? This should absolutely be in it.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15400#comment:6>
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