Still more Constexpr fun (n3469)

[Howard Hinnant]

On Jul 29, 2013, at 1:12 PM, Marshall Clow <mclow.lists at gmail.com> wrote:

> Slouching towards C++14
> Adding constexpr to <chrono>
> 
> -- Marshall
> 
> Marshall Clow     Idio Software   <mailto:mclow.lists at gmail.com>
> 
> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait).
>        -- Yu Suzuki
> <n3469.patch>

Thanks Marshall!

I can't find anything to complain about.  Please commit.  Could I ask a favor?

Could you do a drive-by fix for:

    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR duration() {} // = default;

to implement the required = default if _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS  is not defined?

We have an example in <memory> for one way to do this:

template <class _Tp>
struct _LIBCPP_TYPE_VIS default_delete
{
#ifndef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT = default;
#else
    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT {}
#endif

Thanks,
Howard