[GHC] #7268: Explicit type signatures for top level record pattern matches polymorphism fail

[GHC]

#7268: Explicit type signatures for top level record pattern matches polymorphism
fail
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    Reporter:  TristanAllwood           |       Owner:  simonpj                  
        Type:  bug                      |      Status:  new                      
    Priority:  normal                   |   Milestone:  7.8.1                    
   Component:  Compiler (Type checker)  |     Version:  7.4.1                    
    Keywords:                           |          Os:  Unknown/Multiple         
Architecture:  Unknown/Multiple         |     Failure:  GHC rejects valid program
  Difficulty:  Unknown                  |    Testcase:                           
   Blockedby:                           |    Blocking:                           
     Related:                           |  
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Changes (by MartijnVanSteenbergen):

 * cc: martijn@… (added)


Comment:

 Some more info and examples can be found in #7891.

 Notably, for the program above, an extra indirection makes it ok again to
 give a type signature:

 {{{
 id'' :: a -> a
 id'' = id'
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7268#comment:2>
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