19 declare(strict_types=1);
    27     $transformation = 
$refinery->to()->tupleOf(
    29             new \
ILIAS\
Refinery\To\Transformation\IntegerTransformation(),
    34     $result = $transformation->transform([5, 1]);
    36     return assert([5, 1] === $result);
 
Interface Observer  Contains several chained tasks and infos about them.