Re: [Boost-users] [hash][vc-7_1] warning on boost::hash<std::size_t> [was Re: [multi_index] function object as key extractor?]

From: Filip Konvička (filip.konvicka_at_[hidden])
Date: 2007-03-22 05:22:57

> On Tue, 20 Mar 2007 17:54:53 -0000, Joaquín Mª López Muñoz  
> <joaquin_at_[hidden]> wrote:
>
>   
>>> Maybe it would be better if boost::hash included a size_t version:
>>>
>>>    inline std::size_t hash_value(std::size_t v)
>>>    {
>>>        return v;
>>>    }
>>>
>>> If necessary, in cases where std::size_t == unsigned int, it could
>>> probably use is_same<T,U> to make sure both versions didn't exist and
>>> cause warnings/errors.
>>>       
>
> Sorry, I didn't notice this thread before. This has actually been fixed in  
> 1.34, and 1.35 will have proper suport for 'long long' and 'unsigned long  
> long'. If you can't upgrade when 1.34 is released (which should be soon?),  
> I'd suggest that you add this function to the boost namespace, either in  
> or before the boost headers. It's a pretty nasty hack but the warning is  
> valid so it's worth it.
>   
Great, thanks for the info! I was rather reluctant about disabling that 
warning. Looking forward to 1.34 :-)

Cheers,
Filip