[GHC] #7897: MakeTypeRep fingerprints be proper, robust fingerprints

[GHC]

#7897: MakeTypeRep fingerprints be proper, robust fingerprints
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        Reporter:  simonpj           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  ⊥
       Component:  Compiler          |              Version:  7.6.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by adamgundry):

 Another use case for this is in the `safecopy` package (see
 https://github.com/acid-state/acid-
 state/issues/102#issuecomment-426327014), where it would be useful to be
 able to notice that the developer has changed a type used for binary
 serialization purposes. That said, perhaps a TH/Generics solution would be
 possible, so it may not be worth changing the current semantics of
 fingerprints.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7897#comment:8>
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