Questions about Symfony 2 service container parameters - symfony

Question

1. Passing parameters into the service?
If not already defined in the services.xml (or yaml), is the only way to pass parameter(s) into service is:
$container->setParameter('loader', $loader);
$container->get('myservice');
I suppose this way loader will be available to ALL services, not just "myservice"?
2. Passing an array of objects into the service?
The Template/DelegatingEngine class takes an array of engine object into the constructor, and I dont know how should I define that in the xml file:
public function __construct(array $engines = array())
{
$this->engines = array();
foreach ($engines as $engine) {
$this->addEngine($engine);
}
}
What should I put into the
<service id="myCustomeFramework.TemplateEngine" class="path\to\DelegateEngine" scope="prototype">
<argument>how can i pass an array of engines here?</argument>
</service>

Answer 1

Answer 1
Yes, it will be available for all services that uses that parameter and that are called after setting the parameter.
Answer 2
For passing an array as an argument to a service using xml you have to do it in this way:
<service id="myCustomeFramework.TemplateEngine" class="path\to\DelegateEngine" scope="prototype">
<argument type="collection">
<argument key="key">value</argument>
<argument key="key">value</argument>
<argument key="key">value</argument>
</argument>
</service>