[GHC] #15646: ghci takes super long time to find the type of large fractional number

[GHC]

#15646: ghci takes super long time to find the type of large fractional number
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        Reporter:  Johannkokos       |                Owner:
                                     |  JulianLeviston
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  GHCi              |              Version:  8.4.3
      Resolution:                    |             Keywords:  newcomer
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #5692             |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by JulianLeviston):

 It's worth noting that this MR doesn't include the changes where I
 attempted to move the functions into `GHC.Real`. I stopped doing that
 because it would have involved somehow getting the `FractionalLit` type
 in, too, and I didn't know how to do that while also having it in
 `BasicTypes`.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15646#comment:73>
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