public static function propertyAnnotations($class, $propertyName)
    {
        $class = is_object($class) ? get_class($class) : $class;
        if (!class_exists('ReflectionProperty')) {
            throw new \RuntimeException("Property type of " . $class . "::{$propertyName} cannot be resolved");
        }

        if ($annotations =& self::$propertiesType[$class][$propertyName]) {
            return $annotations;
        }

        if (!($refl =& self::$propertiesRefl[$class][$propertyName])) {
            $getter = self::getter($class, $propertyName);
            $refl = new \ReflectionMethod($class, $getter);
            self::$propertiesRefl[$class][$propertyName] = $refl;
        }

        // todo: smarter regexp
        if (!preg_match_all(
            '~\@([^\s@\(]+)[\t ]*(?:\(?([^\n@]+)\)?)?~i',
            $refl->getDocComment(),
            $annots,
            PREG_PATTERN_ORDER)
        ) {
            return null;
        }
        foreach ($annots[1] as $i => $annot) {
            $annotations[strtolower($annot)] = empty($annots[2][$i]) ? TRUE : rtrim($annots[2][$i], " \t\n\r)");
        }

        return $annotations;
    }