Re: [boost] [range] as_array broken

From: shunsuke (pstade.mb_at_[hidden])
Date: 2007-01-10 23:27:00

Eric Niebler wrote:
> Thorsten Ottosen wrote:
>> Eric Niebler wrote:
>>> Consider the output of the following program:
>>>
>>  >
>>> It seems Boost.Range is still treating arrays of char and wchar_t 
>>> specially. IIRC, we decided long ago that it shouldn't.
>>>
>>> This is on HEAD, BTW.
>> Fixed
> 
> Thanks. You might want to add a test for this as well <nudge>.
> 
> While we're at it, this trivial code fails to compile on msvc-7.1:
> 
>    int rg[5] = {};
>    boost::begin(rg);
> 
> Clearly, it's a compiler bug. But the work-around is simple enough. In 
> range/begin.hpp, the begin() overloads have the following signatures:
> 
>    template< class T >
>    typename range_iterator<T>::type begin( T& r )
> 
>    template< class T >
>    typename range_iterator<const T>::type begin( const T& r )
> 
> If there were defined as follows:
> 
>    template< class T >
>    typename range_mutable_iterator<T>::type begin( T& r )
> 
>    template< class T >
>    typename range_const_iterator<T>::type begin( const T& r )

Another(more generic?) workaround seems known.

template< class T >
typename range_iterator< typename add_const<T>::type >::type
some_algo(T const& rng) {
     // ...
}

I prefer a macro to document this bug... http://tinyurl.com/y2wkq3
Well, this bug seems not only involved in Boost.Range.
VC++7.1 users would need this workaround; everywhere 'T' is deduced as 
array type.

Regards,

-- 
Shunsuke Sogame