New in version 1.2.
Definition
Return Values
A MongoDB\Driver\WriteConcern object.
Example
$database = (new MongoDB\Client)->getDatabase('test', [    'writeConcern' => new MongoDB\Driver\WriteConcern(1, 0, true), ]); var_dump($database->getWriteConcern()); 
The output would then resemble:
object(MongoDB\Driver\WriteConcern)#5 (2) {   ["w"]=>   int(1)   ["j"]=>   bool(true) }