public static function bind($type, $name, array $config = []) {
		$self = static::_object();
		if (!isset($config['fieldName'])) {
			$config['fieldName'] = $self->_relationFieldName($type, $name);
		}

		if (!in_array($type, $self->_relationTypes)) {
			throw new ConfigException("Invalid relationship type `{$type}` specified.");
		}
		$self->_relationFieldNames[$config['fieldName']] = $name;
		$rel = static::connection()->relationship(get_called_class(), $type, $name, $config);
		return $self->_relations[$name] = $rel;
	}