T9774.hs:5:29: error:
    • Couldn't match type ‘Char’ with ‘[Char]’
      Expected: String
        Actual: Char
    • In the second argument of ‘assert’, namely ‘'a'’
      In the first argument of ‘putStrLn’, namely ‘(assert True 'a')’
      In the expression: putStrLn (assert True 'a')