Tag Type C++ code (built in to libHForm/scan_body.cc)
Attributes var=varName Required. Sets the variable name whose value we want to keep track of during the time that it does not have a corresponding HTML Forms widget.
Contained Tags None.
Related Tags This tag must appear in the Body section.

This tag is used internally by RPM when it detects that one of the Public variables in the form does not have a corresponding widget-generating tag (such as Entry, Radio, Checkbox, Menu, FileMenu, or Delta.

If you would like to keep track of a Private variable, then you must do it manually. Simply include a line like this somewhere in the Body section of the document:

  {Hidden var=myPrivateVar}