[boost] [date_time] i/o formatting

From: Yuval Ronen (ronen_yuval_at_[hidden])
Date: 2006-02-25 17:50:04

Hi.
I've used the date_time I/O using facets and found it too complicated. 
The thing that bothers me is that I need to use a facet to specify the 
format string (e.g "HH:MM:SS"). This is burdensome. IMO, using facets is 
fine for defining things which are really locale-related (and are mostly 
constant during the process lifetime) such as the month names in the 
local language. The format is not such a property and can often change 
throughout the application, and as such is much better handled using an 
I/O manipulator:

     cout << time_format("HH:MM:SS") << my_ptime << endl;

or if this is impossible, then

     cout << time_io(my_ptime, "HH:MM:SS") << endl;

which surely is possible.

I think of specifying the format string as similar to specifying the 
printing precision of a float, or specifying that an integer should be 
printed as hex. These are provided as manipulators without the 
complexity of facets (which most users, including me, know very little 
about).

BTW, this is not my original idea. I saw it in a post (don't remember by 
whom) in this mailing list a few months ago.

Thanks,
Yuval