[GHC] #10772: Type operator variable in prefix notation fails

[GHC]

#10772: Type operator variable in prefix notation fails
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              Reporter:  nomeata     |             Owner:
                  Type:  bug         |            Status:  new
              Priority:  normal      |         Milestone:
             Component:  Compiler    |           Version:  7.11
  (Parser)                           |
              Keywords:              |  Operating System:  Unknown/Multiple
          Architecture:              |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
             Test Case:              |        Blocked By:
              Blocking:              |   Related Tickets:
Differential Revisions:              |
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 Hi,

 I’m not sure if this is me misreading the documentation at
 https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/data-type-
 extensions.html#infix-tycons (in which case maybe the wording can be
 improved) or an actual bug. But I would have expected this code

 {{{
 foo :: [(*)] -> Maybe (*)
 foo _ = Nothing
 }}}

 to be equivalent to

 {{{
 foo :: [(*)] -> Maybe (*)
 foo _ = Nothing
 }}}

 at least with `-XNoTypeOperators`. But independent of that flag, with GHC
 HEAD and 7.8, I get
 {{{
 /tmp/foo.hs:1:9: error: Not in scope: type constructor or class ‘*’
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10772>
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