[GHC] #11409: Cannot instantiate literals using TypeApplications

[GHC]

#11409: Cannot instantiate literals using TypeApplications
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        Reporter:  Feuerbach         |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.4.1
       Component:  Compiler          |              Version:  8.0.1-rc1
      Resolution:                    |             Keywords:
                                     |  TypeApplications
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #11352            |  Differential Rev(s):
       Wiki Page:                    |
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Description changed by Iceland_jack:

Old description:

> {{{
> GHCi, version 8.0.1.20160110: http://www.haskell.org/ghc/  :? for help
> Prelude> :set -XTypeApplications -fprint-explicit-foralls
> Prelude> :t 42
> 42 :: forall {a}. Num a => a
> Prelude> 42 @Int
>
> <interactive>:3:1: error:
>     • Cannot not apply expression of type ‘a0’
>       to a visible type argument ‘Int’
>     • In the expression: 42 @Int
>       In an equation for ‘it’: it = 42 @Int
> }}}
>
> (Also, "cannot not" looks like a typo.)

New description:

 Relevant
 [https://www.reddit.com/r/haskell/comments/60seia/type_application_on_literals/
 reddit post].

 ----

 {{{
 GHCi, version 8.0.1.20160110: http://www.haskell.org/ghc/  :? for help
 Prelude> :set -XTypeApplications -fprint-explicit-foralls
 Prelude> :t 42
 42 :: forall {a}. Num a => a
 Prelude> 42 @Int

 <interactive>:3:1: error:
     • Cannot not apply expression of type ‘a0’
       to a visible type argument ‘Int’
     • In the expression: 42 @Int
       In an equation for ‘it’: it = 42 @Int
 }}}

 (Also, "cannot not" looks like a typo.)

--

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11409#comment:18>
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