This template returns the start and end time for a TTML element, based on the begin, end, and dur attributes. It returns each of them as numbers of seconds, as returned by ttml.time.seconds, separated by a comma. Begin and end times are returned as absolute times, relative to the computed range of the parent element. The parent range may be passed in the $range parameter. If the parameter is empty, the parent range is computed automatically by calling this template on the nearest ancestor of $node with a begin attribute.

If both $end and $dur are provided, the end times for each are calculated, and the one that results in the shortest duration is used.

If there is no end time for the element, the string ∞ is used as the end time.