    public function __construct($name) {
        $configLookup = array(
            'rel' => 'AllowedRel',
            'rev' => 'AllowedRev'
        );
        if (!isset($configLookup[$name])) {
            trigger_error('Unrecognized attribute name for link '.
                'relationship.', E_USER_ERROR);
            return;
        }
        $this->name = $configLookup[$name];
    }
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.