+ author: () ->\r
+ new Pettanr.Author({id: @get('author_id')})\r
+ \r
+ is_visible: (operators) ->\r
+ switch super(operators)\r
+ when null\r
+ return true\r
+ when false\r
+ return false\r
+ else\r
+ @get('visible') > 0\r
+ \r
+ symbol_filename: () ->\r
+ \r