The following names are used as terminals in the grammar. They denote classes of tokens, and are defined precisely in Section A.4.3.
Comments and white space follow C++ conventions. A comment either begins with // and ends with the first subsequent newline, or begins with /* and ends with */ (the latter form does not nest). Of course, these delimiters are only recognized outside text literals. White space delimits tokens but is otherwise ignored (except that the Space character, the ASCII character represented by the decimal number 32, is significant within text literals). The grammar prohibits white space other than the Space character within text literals.
The names of the built-in functions begin with an underscore character, and the identifier consisting of a single period (i.e., ``.'') plays a special role in the Vesta SDL. It is therefore recommended that Vesta programs avoid defining identifiers of these forms.