Re: [GHC] #12092: Out-of-scope variable leads to type error, not scope error

26 May 2018

      #12092: Out-of-scope variable leads to type error, not scope error
-------------------------------------+-------------------------------------
        Reporter:  kwf               |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.0.1
  checker)                           |             Keywords:
      Resolution:  fixed             |  TypeApplications
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  warning at compile-time            |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #13834            |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by RyanGlScott):

 * status:  new => closed
 * keywords:   => TypeApplications
 * resolution:   => fixed
 * related:   => #13834

Comment:

 In GHC 8.4, you do in fact get a "Variable not in scope" error:

 {{{
 Bug.hs:5:7: error:
     • Variable not in scope: spam
     • Perhaps you meant ‘span’ (imported from Prelude)
   |
 5 | huh = spam @Int
   |       ^^^^

 Bug.hs:5:7: error:
     • Cannot apply expression of type ‘t1’
       to a visible type argument ‘Int’
     • In the expression: spam @Int
       In an equation for ‘huh’: huh = spam @Int
   |
 5 | huh = spam @Int
   |       ^^^^^^^^^
 }}}

 Of course, there's still the issue that the second part of the error
 message still appears. But that is the subject of #13834, so I'll close
 this ticket in favor of that one.

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12092#comment:3
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