Re: c++0x vs. tr1 type_traits, round 1

[Paolo Carlini <pcarlini at suse dot de>]

Hi,

a couple of quick observations...

> +  template<typename _Tp>
> +    struct has_trivial_default
> +    : public integral_constant<bool, is_pod<_Tp>::value> { };
> +
> +  template<typename _Tp>
> +    struct has_nothrow_default
> +    : public integral_constant<bool, is_pod<_Tp>::value> { };
>  
the final names for those facilities are:

   has_trivial_default_constructor
   has_nothrow_default_constructor
   has_trivial_copy_constructor
   has_nothrow_copy_constructor

(I'm going to change all of them to exploit the front-end traits, 
already available).

In general, these issue about TR1 vs C++0x are nasty. Other traits, for 
example, are undergoing subtle semantic changes (for example, I 
implemented __is_base_of consistently with the C++0x semantics and, as 
you can see, for now, for TR1, I'm adjusting it a bit to the TR1 
semantics); likewise for is_convertible_to, which will be different in 
C+++0x (I'm currently working on the front-end support for it).

I wish we manage to find a decently clean solution, which could also 
mean separate files...

Paolo.