Hoa\Core\Exception\Group supports transactions.

Example:
    $e   = new Hoa\Core\Exception\Group('This is a cluster', 7);
    $e1  = new Hoa\Core\Exception('Test %d', 1, 41);
    $e2  = new Hoa\Core\Exception('Test %d', 2, 42);
    $e3  = new Hoa\Core\Exception('Test %d', 3, 43);
    $e4  = new Hoa\Core\Exception('Test %d', 4, 44);
    $e[] = $e1;

    $e->beginTransaction();
    $e[] = $e2;
    $e[] = $e4;
    $e->cancelTransaction();

    var_dump(count($e)); // int(1)
Format spaces when raising a group of exceptions.