unordered containers emplace

[François Dumont]

On 12/07/2011 01:01 PM, Paolo Carlini wrote:
> Hi,
>> Hi
>>
>>     This is the implementation of emplace and emplace_hint for 
>> unordered containers. For the moment in emplace_hint the hint 
>> iterator is not considered like in the current insert with hint 
>> implementation.
> detail: for consistency with _M_insert, I think we should swap the 
> arguments of _M_emplace, last true_type / false_type.
     This is what I did to begin but it failed to compile, g++ do not 
know then when to stop considering arguments as part of the _Args.... I 
consider it was a normal limitation of using variadic templates, if so I 
can invert parameters of _M_insert to have consistency.
>
> Much more importantly, I don't think we are doing the right thing for 
> map / multimap; honestly I cannot say to have followed in any special 
> detail the standardization of the piecewise_construct_t things, at the 
> corresponding ISO Meetings, but I think we have to involve that pair 
> constructor in this case. I'm adding Jon and Chris in CC for you to 
> have more help on this, please also have a look to various papers 
> authored by Pablo Halpern et al over the last 2/3 years.
     Good point, I hadn't notice this potential issue. I am lucky that 
the library is well designed making my patch not so bad. I will add the 
necessary tests and resubmit a patch.

François