Updating object properties in twig
You can do it by merging objects:
{% set object = object|merge({'property1': 'somenewvalue'}) %}
Twig has a do tag that allows you to do that.
{% do foo.setBar(value) %}
A possible way to set a property is to create a method in the object which actually creates new properties:
class Get extends StdClass
{
protected function setProperty($name,$value = null)
{
$this->$name = $value;
}
}