testsuite/tests/deSugar/should_compile/T3263-1.hs


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-- #3263.  New kind of warning on ignored monadic bindings

module T3263 where

nullM :: IO ()
nullM = return ()

nonNullM :: IO Int
nonNullM = return 10

-- No warning
t1 = do
  nonNullM

-- No warning
t2 = nonNullM

-- No warning
t3 = do
  nullM
  nonNullM

-- Warning
t4 = do
  nonNullM
  nullM

-- No warning
t5 = do
  _ <- nonNullM
  nullM

-- Warning
t6 = mdo
  nonNullM
  nullM