[GHC] #5855: Computation Hangs Using PolyKinds

[GHC]

#5855: Computation Hangs Using PolyKinds
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  Reporter:  paf31          |          Owner:                  
      Type:  bug            |         Status:  closed          
  Priority:  normal         |      Milestone:                  
 Component:  Compiler       |        Version:  7.4.1           
Resolution:  invalid        |       Keywords:                  
        Os:  Windows        |   Architecture:  Unknown/Multiple
   Failure:  Runtime crash  |     Difficulty:  Unknown         
  Testcase:                 |      Blockedby:                  
  Blocking:                 |        Related:                  
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Comment(by paf31):

 I had assumed that fold being an exhaustive pattern match, laziness would
 be the default behavior, but I missed hmap and compose.

 Thank you,
 Phil.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5855#comment:3>
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