[GHC] #2900: Confusing error message for monadic function with wrong number of arguments

[GHC]

#2900: Confusing error message for monadic function with wrong number of arguments
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  Reporter:  tim                      |          Owner:                  
      Type:  bug                      |         Status:  closed          
  Priority:  normal                   |      Milestone:  _|_             
 Component:  Compiler (Type checker)  |        Version:  6.10.1          
Resolution:  fixed                    |       Keywords:                  
        Os:  Unknown/Multiple         |   Architecture:  Unknown/Multiple
   Failure:  None/Unknown             |     Difficulty:  Unknown         
  Testcase:                           |      Blockedby:                  
  Blocking:                           |        Related:                  
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Changes (by monoidal):

  * status:  new => closed
  * failure:  => None/Unknown
  * resolution:  => fixed


Comment:

 GHC 7.6 gives

 {{{
 X.hs:4:1:
     Couldn't match type `()' with `m0 ()'
     Expected type: t0 -> m0 ()
       Actual type: m ()
     The equation(s) for `foo' have two arguments,
     but its type `Int -> m ()' has only one
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2900#comment:3>
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