Backus-Naur Form (BNF) Semantics

The following sections we will define the language along with the supporting concepts.

The BNF semantics used are as follows:

1.

Words inside double quotes (``word'') represent literal words themselves (these are called terminals). The phrase double_quote is used to represent the double-quote character itself. An example literal: ``if''.

2.

Words outside double quotes (possibly with underscores) represent syntactic categories (i.e. nonterminals). An example nonterminal: if_statement.

3.

Syntactic categories are defined using the form: syntactic_category ::= definition

4.

Square brackets ([ ]) surround optional items.

5.

Curly brackets ({ }) surround items that can repeat zero or more times.

6.

A vertical line (|) separates alternatives.