[GHC] #1809: type families: difference in type-checking between compile-time and run-time

[GHC]

#1809: type families: difference in type-checking between compile-time and run-
time
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 Reporter:  guest     |          Owner:  chak       
     Type:  bug       |         Status:  new        
 Priority:  normal    |      Milestone:  6.10 branch
Component:  Compiler  |        Version:  6.8        
 Severity:  normal    |     Resolution:             
 Keywords:            |     Difficulty:  Unknown    
 Testcase:            |   Architecture:  x86        
       Os:  Linux     |  
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Changes (by ganesh):

 * cc: ganesh at earth.li (added)

Comment:

 An even simpler example:


 {{{
 module Test6 where

 type family Id a

 type instance Id Int = Int

 five :: Id Int
 five = 5

 -- This typechecks ok, but show five at the ghci prompt doesn't
 foo = show five
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1809#comment:4>
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