[GHC] #12529: Error message: visible type application of constructor/variable that is not in scope

[GHC]

#12529: Error message: visible type application of constructor/variable that is not
in scope
-------------------------------------+-------------------------------------
           Reporter:  Iceland_jack   |             Owner:
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.0.1
           Keywords:                 |  Operating System:  Unknown/Multiple
  TypeApplications                   |
       Architecture:                 |   Type of failure:  Incorrect
  Unknown/Multiple                   |  warning at compile-time
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 If I use an identifier not in scope:

 {{{
 $ ghci -ignore-dot-ghci
 GHCi, version 8.0.1: http://www.haskell.org/ghc/  :? for help
 Prelude> p

 <interactive>:1:1: error: Variable not in scope: p
 Prelude> P

 <interactive>:2:1: error: Data constructor not in scope: P
 }}}

 Using visible type application:

 {{{
 $ ghci -ignore-dot-ghci -XTypeApplications
 GHCi, version 8.0.1: http://www.haskell.org/ghc/  :? for help
 Prelude> p @Int

 <interactive>:1:1: error:
     • Cannot apply expression of type ‘t0’
       to a visible type argument ‘Int’
     • In the expression: p @Int
       In an equation for ‘it’: it = p @Int
 Prelude> P @Int

 <interactive>:2:1: error:
     • Cannot apply expression of type ‘t0’
       to a visible type argument ‘Int’
     • In the expression: P @Int
       In an equation for ‘it’: it = P @Int
 }}}

 I would prefer these error messages to be the same as the first two:
 thoughts?

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12529>
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