protected function markVoidElements(DOMDocument $ir)
	{
		foreach ($this->query('//element') as $element)
		{
			// Test whether this element is (maybe) void
			$elName = $element->getAttribute('name');
			if (strpos($elName, '{') !== false)
			{
				// Dynamic element names must be checked at runtime
				$element->setAttribute('void', 'maybe');
			}
			elseif (preg_match($this->voidRegexp, $elName))
			{
				// Static element names can be checked right now
				$element->setAttribute('void', 'yes');
			}
		}
	}