static function either($a, $b)
 {
     return tink_core__Future_Future_Impl_::first(tink_core__Future_Future_Impl_::map($a, isset(tink_core_Either::$Left) ? tink_core_Either::$Left : array("tink_core_Either", "Left"), false), tink_core__Future_Future_Impl_::map($b, isset(tink_core_Either::$Right) ? tink_core_Either::$Right : array("tink_core_Either", "Right"), false));
 }