Macro:	alistp - determine if value of a variable might be an alist

Synopsis:
	status alistp(mixed variable)

Description:
	Check if the value of a variable MIGHT be an alist: It tests, if it
	is an array and if the first element is an array, too.

Return value:
	true if the values of the variable are likely to be a valid alist.

Examples:
	string **mylist1 = ({
		({ "blah", "foo" }),
		({ "value1", "value2" })
	});
	return alistp(mylist1); // would return true

	string **mylist2 = ({
		({ "foobar", "barfoo" })
	});
	return alistp(mylist2); // would return true, too,
				// even it is no alist

Note:
	This is not a simulated efun but a MACRO defined in /include/auto.h .

See also: LPC/alists