SYNOPSIS
	closure symbol_variable(string arg)
	closure symbol_variable(symbol arg)
	closure symbol_variable(int arg)

DESCRIPTION
	Constructs an identifier (lfun) closure from the global
	variable arg of this_object(). The variable may be given as a
	symbol, by name or by its ordinal number in the objects
	variable table.
	If there is no such variable, or if it is not visible outside
	the object, 0 is returned.

	If the argument is an integer, and the variable is inherited
	and private in the inherited object (i.e. hidden), then a
	privilege violation will occur.

HISTORY
	Enabled since 3.2.1@8

EXAMPLES
	int base;
	int var;
	symbol_variable("var")		-> #'<this_object>->var
	symbol_variable(0)		-> #'<this_object>->base

SEE ALSO
	lambda(E), quote(E), symbol_function(E)
