[GHC] #11050: [bug] ModOrigin: hidden module redefined

[GHC]

#11050: [bug] ModOrigin: hidden module redefined
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           Reporter:  codeonwort     |             Owner:
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:  7.10.3
          Component:  Compiler       |           Version:  7.10.2
           Keywords:                 |  Operating System:  Linux
       Architecture:  x86_64         |   Type of failure:  Compile-time
  (amd64)                            |  crash
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 {{{#!hs
   1 import Haste
   2 import Haste.DOM
   3 import Haste.Graphics.Canvas
   4 import Control.Monad
   5
   6 mkCanvas width height = do
   7   canvas <- newElem "canvas"
   8   setProp canvas "width" $ show width
   9   setProp canvas "height" $ show height
  10   let conf = [("display", "block"), ("border", "1px solid black"),
 ("margin", "0px auto 0 aut    o"), ("backgroundColor", "black")]
  11   mapM_ (\(style, value) -> setStyle canvas style value) conf
  12   return canvas
  13
  14 picture = fill $ rect (0, 0) (600, 600)
  15
  16 main = do
  17   canv <- mkCanvas 600 600
  18   addChild canv documentBody
  19   Just canv <- getCanvas canv
  20   render canv picture
 }}}

 ------------------------------------------------------------------------
 hello.hs:18:3: Warning:hastec: hastec: panic! (the 'impossible' happened)
   (GHC version 7.10.2 for x86_64-unknown-linux):
         ModOrigin: hidden module redefined

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
 ------------------------------------------------------------------------

 I was following the tutorial on http://ifeanyi.co/posts/client-side-
 haskell/ and got this bug.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11050>
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