[GHC] #14255: Type-indexed type fingerprints

[GHC]

#14255: Type-indexed type fingerprints
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        Reporter:  dfeuer            |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Core Libraries    |              Version:  8.2.1
      Resolution:                    |             Keywords:  Typeable
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 dfeuer):

 Whether or not we can reduce the size of the trusted code base, I think
 this is a good thing to offer. In particular, applications that use
 deserialized `Dynamic` very heavily, but that ''don't'' use `dynApply` or
 other reflection-based operations can be much more efficient if they stick
 to fingerprints instead of full `TypeRep`s. Indexing these fingerprints by
 type supports a friendly and modern, though necessarily limited, API.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14255#comment:4>
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