T9774.hs:5:17: error:
    • Couldn't match type ‘Char’ with ‘[Char]’
      Expected type: String
        Actual type: Char
    • In the first argument of ‘putStrLn’, namely ‘(assert True 'a')’
      In the expression: putStrLn (assert True 'a')
      In an equation for ‘foo’: foo = putStrLn (assert True 'a')