ChainElement::__construct

public function __construct($element, $parameters = array())
{
	if ($element instanceof Reference)
	{
		$this->type = 2;
	}
	elseif (is_array($element)
		&& $element[0] instanceof Entity
		&& $element[1] instanceof Reference
	)
	{
		$this->type = 3;
	}
	elseif ($element instanceof Entity)
	{
		$this->type = 4;
	}
	elseif ($element instanceof Field)
	{
		$this->type = 1;
	}
	else
	{
		throw new SystemException(sprintf('Invalid value for QueryChainElement: %s.', $element));
	}

	$this->value = $element;
	$this->parameters = $parameters;
}