Create a service and put your common functionality in it. For example, you can name it ArrayService
and register it in the container as array.service
. You can then access this service from controllers via
$this->get('array.service');
and from commands via
$this->getContainer()->get('array.service');
So, your code will look something like this:
$element = $this->get('array.service')->last($array); // or ->arrayLast($array)
If you need the same functionality across several projects, make a bundle with that service and add it to the deps
file of each project. Then it will be installed when you run the bin/vendors install
script.