[GHC] #7731: Add "source" button for instances in Hackage

[GHC]

#7731: Add "source" button for instances in Hackage
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Reporter:  polkovnikov.ph    |          Owner:                   
    Type:  feature request   |         Status:  new              
Priority:  normal            |      Component:  Documentation    
 Version:                    |       Keywords:  hackage, instance
      Os:  Unknown/Multiple  |   Architecture:  Unknown/Multiple 
 Failure:  None/Unknown      |      Blockedby:                   
Blocking:                    |        Related:                   
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 There's no "Source" button to the right of the TC instance documentation
 in Hackage.

 I can see there're some structural problems with source navigation in
 Hackage (i.e. wrong files shown when dealing with preprocessor). I suppose
 it happens, because the only file it looks into is the one currently
 opened. This may be a real problem due to the scoping of instances. I'm
 rather unsure whether I should file an another ticket for this.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7731>
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