This is more of a micro-optimisation question which is why I posted it here rather than StackOverflow.I have many instances of this sort of code in my Symfony 2 application where I get the CourseManager service and call method in it. My question is - should I grab the service and stick it in a variable inside the method or is it better and more efficient to call $this->get('CourseManager') as I am doing or is this way sub-optimal?    $params = [        'site' => $site,        'currenttab' => 'golf',        'addOns' => $this->get('CourseManager')->getAddOns($site),        'lastRetryDate' => $this->get('CourseManager')->getLastRetryDate($site),        'expectedDate' => $this->get('CourseManager')->getExpectedDate($site)    ];
Should I stick a service in a variable or reference it multiple times
php;optimization;services;symfony