Re: [boost] [gsoc 2013] draft proposal for chrono::date

3 May 2013


      On 5/3/2013 8:30 AM, Vicente J. Botet Escriba wrote:
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Le 03/05/13 13:52, Rob Stewart a écrit :
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On May 3, 2013, at 3:47 AM, "Vicente J. Botet Escriba"
 wrote:
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You can even handle other orders that way:
date(month, unsigned, year);
date(month, day, unsigned);
date(unsigned, day, month);
date(year, unsigned, month);
One can also be explicit for both day and year:
date(year, month, day);
date(month, day, year);
date(day, month, year);
date(day, year, month);
I don't think that the constructor should support different orderings.
It could, easily, so why not? Different locales have different
preferred orderings. All can learn to use the descending magnitude
order, but a little flexibility, without ambiguity, would be nice.
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I'm assuming explicit constructors for day and year, of course.
Of course. And implicit conversion to his representation, so that
date(2013, may, 3, no_check)
is yet valid.
That's where I disagree. If you have explicit constructors for year
and day, and no constructor accepting two ::rep arguments, then your
example won't compile.
That's also what enables support for other argument orders.
The no_check constructor allows only year,month,day order of arguments.
If the user know that the date is valid it can know the order. This is a
low level function.
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We could have a factory make_date function that doesn't checks the
validity of the date and avoids the no_check parameter
make_ymd_date(2013, may, 3)
I don't understand what no_check has to do with such a function. Add
an overload that accepts no_check_t to get that.
The name is not the good one.
make_unchecked_date(2013, may, 3);
or
make_valid_date(2013, may, 3);
This reminds me of the constexpr date constructor sketched out at:

http://akrzemi1.wordpress.com/2011/05/06/compile-time-computations/

Re: [boost] [gsoc 2013] draft proposal for chrono::date

Michael Marcin