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


  def zip_test
    [{'foo, 1}, {'bar, 2}] = ['foo, 'bar].zip([1, 2])
    self.assert_error 'function_clause, -> ['foo].zip([1, 2])
  end

  def unzip_test
    {['foo, 'bar], [1,2]} = [{'foo, 1}, {'bar, 2}].unzip
    self.assert_error 'function_clause, -> [{'foo, 0}, 'bar].unzip
  end

  def zipwith_test
    [5,7,9] = [1,2,3].zipwith([4,5,6], -> (x,y) x + y)
    self.assert_error 'function_clause, -> [1,2,3].zipwith([1,2], -> (_,_) 0)
  end

  def head_test
    1  = [1,2,3].head
    1  = [1].head
    self.assert_error 'badarg, -> [].head
  end

  def tail_test
    [2,3] = [1,2,3].tail
    [2] = [1,2].tail
    [] = [1].tail
    self.assert_error 'badarg, -> [].tail
  end

  def uniq_test

      true = list.include?(x)
    end

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