Re: [boost] Problem with range (make_iterator_range)?

From: Shunsuke Sogame (mb2act_at_[hidden])
Date: 2006-05-30 14:26:55

Thorsten Ottosen wrote:
> Neal Becker wrote:
>> Thorsten Ottosen wrote:
>>
>>
>>> Neal Becker wrote:
>>>
>>>> #include <boost/range.hpp>
>>>> #include <vector>
>>>>
>>>> template<typename in_t, typename out_t>
>>>> void copy (in_t const& in, out_t &out) {}
>>> What makes you think you can bind a temporary to
>>> an non-const reference (out)?
>>>
>>
>> Yeah, same old problem.  I think the c+ standard should be changed.
> 
> Well, && will help some.
> 
>>  It's
>> quite clear (to me) that this is an important use of the range concept.
> 
> I think the algorothm is wrong in this case. I would go for
> 
> template< class SinglePassRange, class WritableForwardRange >
> void overwrite( const SinglePassRange&, WriteForwardRange& );
> 
> template< class SinglePassRange, class WritableForwardRange >
> void overwrite( const SinglePassRange&, const WriteForwardRange& );

If you don't want to write two overloads
(or if you want to use a function that returns non-const-qualifed 
iterator_range).
the "official" workaround maybe looks like...

     int main() {
       std::vector<int> out (2);
       copy (boost::make_iterator_range (out.begin(), out.begin()+2),
         boost::lambda::make_const(boost::make_iterator_range 
(out.begin(), out.begin()+2)) );
     }

-- 
Shunsuke Sogame