exist:

Synopsis: Check the existence of a variable

Syntax:	exist ( VAR )

Description:

	The exist function returns TRUE (1) if VAR exists, and FALSE
	(0), if VAR does not exist. VAR is any valid variable name.

	If you need to know if a variable exists, and if it is a
	function or data, then use the exist function in conjunction
	with the class or type functions.

See Also: class, type, who, what
