[GHC] #3480: Easily make Typeable keys pure, so that Typeable can be handled efficiently across communications

[GHC]

#3480: Easily make Typeable keys  pure, so that Typeable can be handled
efficiently across communications
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    Reporter:  guest                 |        Owner:                  
        Type:  task                  |       Status:  new             
    Priority:  normal                |    Milestone:  6.14.1          
   Component:  libraries/base        |      Version:                  
    Severity:  trivial               |   Resolution:                  
    Keywords:  Typeable, efficiency  |   Difficulty:  Unknown         
    Testcase:                        |           Os:  Unknown/Multiple
Architecture:  Unknown/Multiple      |  
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Comment (by simonmar):

 Replying to [comment:2 simonpj]:

 > Neither of these give constant-time comparison of `TypeRep`s, but I
 doubt that such comparisons are going to be in the inner loop of any
 program.  And both fix (1) above

 Aren't such comparisons in the inner loop of SYB traversals?

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3480#comment:3>
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