 
   ## Examples
 
-    !1        #=> false
-    ![1,2,3]  #=> false
-    !false    #=> true
-    !nil      #=> true
+      !1        #=> false
+      ![1,2,3]  #=> false
+      !false    #=> true
+      !nil      #=> true
 
   """
   defmacro !arg


  ## Example

     tuple = { :foo, :bar, 3 }
     elem(tuple, 1) #=> :bar

  """
  defmacro elem(tuple, index) when is_integer(index) do


  ## Example

      tuple = { :foo, :bar, 3 }
      setelem(tuple, 0, :baz) #=> { :baz, :bar, 3 }

  """
  defmacro setelem(tuple, index, value) when is_integer(index) do
