calendar object
This method returns the number of months between two dates.
double diff_months(calendar@ object)
Parameters:
object
The handle to another valid calendar object.
Return value:
The difference between the current calendar's date and the date of the passed calendar object handle in months.
Remarks:
Unlike diff_years, this method returns an integer representation of the difference.
Example:

    // Find out the number of months between October 7, 1767 and now.

    void main()
    {
    calendar test;
    calendar now;
    test.set(1767, 10, 7, 9, 0, 0);
    double diff=test.diff_months(now);
    alert("diff_months", "There are "+diff+" months between October 7, 1767 and now.");
    }