[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
-------------------------------------+-------------------------------------
        Reporter:  Johannkokos       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  GHCi              |              Version:  8.4.3
      Resolution:                    |             Keywords:  type
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Johannkokos):

 The problem seems to be specific to scientific notation literals. On GHCi,
 Both
 {{{
 10^1000000 :: Double
 }}}
 and
 {{{
 :t 10^1000000 :: Double
 }}}

 terminate near-instantly, while there is a noticeable delay with
 {{{
 1e1000000 :: Double
 }}}
 and
 {{{
 :t 1e1000000 :: Double
 }}}
 .

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-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15646#comment:1>
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