doIssue.lean:2:2: error: application type mismatch
  do 
    pure x 
    IO.println x
argument
  fun (x_1 : PUnit) => IO.println x
has type
  PUnit → IO Unit
but is expected to have type
  Nat → IO Unit
doIssue.lean:10:2: error: application type mismatch
  do 
    pure (Array.set! xs 0 1)
    IO.println xs
argument
  fun (x : PUnit) => IO.println xs
has type
  PUnit → IO Unit
but is expected to have type
  Array Nat → IO Unit
doIssue.lean:18:2: error: application type mismatch
  do 
    pure (Array.set! xs 0 1)
    IO.println xs
argument
  fun (x : PUnit) => IO.println xs
has type
  PUnit → IO Unit
but is expected to have type
  Array Nat → IO Unit