Metasyntax for functions

Representation	Meaning	Examples
UPPERCASE LETTERS	Designate keywords; some keywords begin with an *	POSITION = *FIRST
=	Links an operand name to its operand values	STREAM = *COMMAND / *DATA
/	Separates alternative operand values	STREAM = *COMMAND / *DATA
Underscoring	Designates the default value of an operand	DIRECTION = *FORWARD / RESERVE
expression	Any expression	EXPRESSION = expression
string_expression	Expression that returns a string	STRING = string_expression
arithm_expression	Expression that returns a numeric value	INTEGER = arithm_expression
integer	Integer (integer value)	START = 1 / integer
character	Character in EBCDI code	FILL-BYTE = character
msg_id	Seven-character message code	MSD-IDENTIFICATION = msg_id