   def flatten_lists_test
     [1,2,3] = [[1,2,3]].flatten_lists
     [1,2,3] = [[1],[2],[3]].flatten_lists
-    self.assert_error 'badarg, -> [1,2,3].flatten_lists
+    assert_error 'badarg, -> [1,2,3].flatten_lists
   end
 
   def each_test

  end

  def fold_test
      addfun = -> (e, acc) e + acc
      "bazbarfoo" = ["foo", "bar", "baz"].foldl("", addfun)
      "foobarbaz" = ["foo", "bar", "baz"].foldr("", addfun)
  end

  def flatten_test

      true = list.include?(x)
    end

    assert_error { 'badmatch, true }, do
      list.each -> (x) false = list.include?(x)
    end
  end
