This section describes the notation used in the Eiffel syntax specification .
Every construct is either a terminal or a non-terminal .
A terminal construct has no further syntactical structure. In contrast, a non-terminal construct is defined in terms of other constructs. Reserved Words Reserved words are keywords or predefined names such as inherit or Result . The notation described here has its own symbols as well. Productions To understand a non-terminal, a formal description of the structure of this construct is needed.