parameters: (self, visitor)
docstring: Add a visitor to the list of visitors.
          @param visitor: the visitor to add, must be derived from AbstractVisitor.
docstring_summary: Add a visitor to the list of visitors.
docstring_tokens: Add a visitor to the list of visitors .
function: def addVisitor(self, visitor):
          """
          Add a visitor to the list of visitors.
          @param visitor: the visitor to add, must be derived from AbstractVisitor.
          """
          if issubclass(visitor.__class__, AbstractVisitor.AbstractVisitor):
              self.__visitor_list.append(visitor)
          else:
              DEBUG.error(
                  "HtmlStartPage.addVisitor(v) - the given visitor is not a subclass of AbstractVisitor!"
              )
              raise Exception(
                  "HtmlStartPage.addVisitor(v) - the given visitor is not a subclass of AbstractVisitor!"
              )
function_tokens: def addVisitor ( self , visitor ) : if issubclass ( visitor . __class__ , AbstractVisitor . AbstractVisitor ) : self . __visitor_list . append ( visitor ) else : DEBUG . error ( "HtmlStartPage.addVisitor(v) - the given visitor is not a subclass of AbstractVisitor!" ) raise Exception ( "HtmlStartPage.addVisitor(v) - the given visitor is not a subclass of AbstractVisitor!" )