testsuite/tests/ghc-regress/typecheck/should_fail/mc20.hs


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-- Checks that the ordering constraint on the implicit groupWith is respected

{-# OPTIONS_GHC -XMonadComprehensions -XTransformListComp #-}

module ShouldFail where

data Unorderable = Gnorf | Pinky | Brain

foo = [ ()
      | x <- [Gnorf, Brain]
      , then group by x
      ]