[pdf-devel] Re: Calendar spans

[jemarch]

   > Using the precedence rule first we add 1 year to 2007-01-31 resulting
   > in 2008-01-31. Then we add 1 month (February in a leap year) resulting
   > in 2008-02-29.
   > 
   > What do you think?

   Well... don't really like it. This means that there are three different 
   time origins for which the calendar time span gives the same result... 
   isn't it?

   29 January 2007 + (1 year + 1 month) = 29 February 2008
   30 January 2007 + (1 year + 1 month) = 29 February 2008
   31 January 2007 + (1 year + 1 month) = 29 February 2008

Yes. If we are talking about months then these three operations should
yield the same result. Just imagine you should make the same operation
to calculate the payments for the DSL connection that you pay monthly
:)

Anyway I would not worry about that. From the Adobe PDF SDK Reference:
 
  Note: There is some ambiguity in a calendar time span; to add an
        exact time span (for example, 2592000 seconds rather than one
        month), use ASDateAddTimeSpan().

It seems we are facing exactly the same problem :)