How to get all action variables

For my programming work, I use symfony framework. It has a funny system of passing variables from actions to templates: you just set the variable as a property of your action object and it automatically becomes available in template that is used to render results. So, there is a bunch of variables you can use, but no way of getting the whole array of them. This line will do the trick:

$vars = $sf_context->getActionStack()->getLastEntry()->getActionInstance()->getVarHolder()->getAll();