/*
 *  call-seq:
 *     mod.class_variables   => array
 *  
 *  Returns an array of the names of class variables in <i>mod</i> and
 *  the ancestors of <i>mod</i>.
 *     
 *     class One
 *       @@var1 = 1
 *     end
 *     class Two < One
 *       @@var2 = 2
 *     end
 *     One.class_variables   #=> ["@@var1"]
 *     Two.class_variables   #=> ["@@var2", "@@var1"]
 */

VALUE
rb_mod_class_variables(obj)
    VALUE obj;
{
    VALUE ary = rb_ary_new();

    for (;;) {
	if (RCLASS(obj)->iv_tbl) {
	    st_foreach_safe(RCLASS(obj)->iv_tbl, cv_i, ary);
	}
	obj = RCLASS(obj)->super;
	if (!obj) break;
    }
    return ary;
}