functional and type_traits cleanup

[Jonathan Wakely]

On 6 April 2013 21:03, Daniel Krügler wrote:
> 2013/4/6 Jonathan Wakely <jwakely.gcc@gmail.com>
>>
>
>> > But the version with the default template parameter is fine and more
>> > consistent with the other helpers implementation so, adopted! Here is an
>> > other version of the patch for validation.
>> >
>> >     Daniel, I agree that inheritance with integral_constant is not as
>> > obvious as before but it is still there and it is just what the compiler
>> > need.
>>
>> I assume Daniel's reply was an HTML mail and didn't make it to the
>> list, was there an objection to the change or a general comment?
>
> Yes, I got a reply that my response was not accepted due to html
> content. I hope this one gets into it.

It did: http://gcc.gnu.org/ml/libstdc++/2013-04/msg00031.html

> My response was more like a
> general comment: My apprehension is that I after these changes not all
> predicate type traits do satisfy the Library requirement anymore that
> they still derive from std::integral_constant. But I have not checked
> that individually.

They should all do, because the types that used to define a 'value'
member all now define a 'type' as a typedef for either true_type or
false_type.

> Thanks Jonathan. The text above more or less reflects the content of
> my previous comment. I think I have no formal objection to the
> changes, but after they have been applied I would like to do a more
> rigorous test of the inheritance requirement.

That wouldn't hurt, but I agree it shouldn't prevent the patch going in.

François, please go ahead and commit it, thanks.