Re: [boost] Re: Date-Time

From: Rob Stewart (stewart_at_[hidden])
Date: 2004-04-19 13:57:03

From: "Jeff Garland" <jeff_at_[hidden]>
> 
> Bottom line, if you want reversability at the date level everything needs to
> be done in terms of days and weeks.

Right.

> 5) Implementing LAST-1, LAST-2, etc
> At the very beginning of this thread I agreed that having functions like:
>   date d(...);//arbitrary date
>   date fd = first_date_of_month(d);
>   date ld = last_date_of_month(d);
> 
> would be valueable additions. LAST-2 can be trivially implemented for fully
> specified dates as follows:
> 
>   days_before_end_of_month(const date& d, days days_before)
>   {
>      return last_date_of_month(d) - days_before;
>   }   

That generates such a date, but doesn't carry the "n days before
the end of the month" concept along with it.  That is, the idea
was to apply the concept to any month and year pair to get "n
days before the end."

> However, it might be useful to have another date generator which would not
> require a full date and could represent the last day of the month variants. 
> I'm thinking something like:
> 
>   last_day_of_month ldom; 
>   date d = ldom.getDate(2003, Feb); //feb 28
>   before_last_day_of_month ldom(2); 
>   date d = ldom.getDate(2003, Feb); //feb 26

That provides the means to overload the date ctors with the
concept.

-- 
Rob Stewart                           stewart_at_[hidden]
Software Engineer                     http://www.sig.com
Susquehanna International Group, LLP  using std::disclaimer;