[boost] Re: Quick thought on Date-Time

From: David Abrahams (dave_at_[hidden])
Date: 2004-04-25 17:43:03

"Jeff Garland" <jeff_at_[hidden]> writes:

> On Sun, 25 Apr 2004 17:03:18 -0400, David Abrahams wrote
>
>> >> So maybe a new type should be made that just represents year & 
>> >> month.  Every year still only has 12 months.  Of course, your 
>> >> problem comes back if you want to mix days in.
>> >
>> > Exactly, and I don't know what I would do with this type without mixing them
>> > back in...
>> 
>>     if (some_date.is_in(Jun/2004))
>>        std::cout << "that's a hot one!";
>
> You didn't need to invent a type to do this

The type is that of Jun/2004

>  -- you just added a function to the date.  You would have to
> reverse it to be what Daryle is suggesting:
>
>  date d(...);
>  some_month_type x(2004, Jun);
>  x.contains(d);

I don't see how they differ, where types are concerned.  You just
changed how the function is invoked.

> But we already have date_period for this:
>  date start_of_month(...), end_of_month(...);
>  date_period dp(start_of_month, end_of_month); 
>  dp.contains(d);

That looks painful, though I don't neccessarily understand it.

> So why not a date_period generator function instead?
>   date_period make_month_period(greg_year y, greg_month m);
> Then it would be:
>   date_period dp = make_month_period(2004, Jun);
>   if (dp.contains(d))  // or is_after, is_before, ...

Also painful-looking.

-- 
Dave Abrahams
Boost Consulting
http://www.boost-consulting.com