The conventions use different font attributes for different components of the syntax. The symbols and fonts are as follows:
Italic type indicates nonterminals.
Terminals in bold type are literal reserved words and symbols that must be entered as shown. Characters in this context are always case sensitive.
Nonterminals followed by opt are always optional.
Characters in the set described or listed in this typeface can be used as terminals in statements.
A colon (:) following a nonterminal introduces its definition. Alternative definitions are listed on separate lines.