[GHC] #7788: Recursive type family causes <<loop>>

[GHC]

#7788: Recursive type family causes <<loop>>
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              Reporter:  shachaf     |            Owner:  simonpj
                  Type:  bug         |           Status:  new
              Priority:  high        |        Milestone:  7.10.1
             Component:  Compiler    |          Version:  7.6.2
  (Type checker)                     |         Keywords:
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:              |       Difficulty:  Unknown
  Unknown/Multiple                   |       Blocked By:
       Type of failure:  Incorrect   |  Related Tickets:
  result at runtime                  |
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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Comment (by simonpj):

 Does anyone actually care about programs with non-terminating type
 computations?

 The type inference engine makes no claim to be a lazy evaluator.  So if
 you write non-terminating type-level expressions, the compiler may loop.

 I agree that it might be more puzzling if the compiler succeeds but the
 program loops at runtime. But that doesn't seem to be happening right now.

 If this matters to anyone, sing out. Otherwise I'm going to leave it.

 Simon

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7788#comment:5>
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