Re: Definitions of date arithmetic

Oct. 10, 1998

      Paul Eggert writes:
...
The same as 1 month before 31 March.
Okay. You can easily implement that on top of something like mktime():

   void month_add(struct caldate *out,struct caldate *in,int m)
   {
     *out = *in;
     out->month += m;
     normalize(out);

     if (out->day != in->day) {
       out->day = FIRST - 1;
       normalize(out);
     }
   }

This example certainly doesn't convince me that mktime()'s handling of
invalid dates is a bad thing.

---Dan
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Re: Definitions of date arithmetic

D. J. Bernstein