fourmolu-0.4.0.0: data/examples/declaration/value/function/comprehension/transform-monad-four-out.hs

{-# LANGUAGE MonadComprehensions #-}
{-# LANGUAGE TransformListComp #-}

quux' xs ys =
    [ ( x
      , y
      )
    | x <- xs
    , y <- ys
    , then group by
        -- First comment
        ( x
            + y
        )
      using
        -- Second comment
        groupWith -- Third comment
    ]