When you want to restore the previous output after using push_output, simply call the subroutine pop_output. If the output type was a string, pop_output will return the string (containing all of the output); otherwise, the return value is not useful.
Usually, you will want to use push_output in the start handler for an element or subdocument entity, and pop_output in the end handler.
David Megginson <dmeggins@aix1.uottawa.ca>