Re: [Boost-users] [multiarray] problems passing views by reference

Subject: Re: [Boost-users] [multiarray] problems passing views by reference
From: Ronald Garcia (rxg_at_[hidden])
Date: 2010-01-14 16:06:07

Thanks for the contribution Rhys.  I think it will make a fine  
addition to MultiArray.

Best,
Ron

On Jan 13, 2010, at 11:48 AM, Rhys Ulerich wrote:

>> The problem might be the body of fill_functor for the general  
>> case.  "*i"
>> will produce a temporary (a subarray), which you are then trying to  
>> pass
>> immediately by reference to the smaller fill_functor case.  C++  
>> doesn't let
>> you pass temporaries by reference, which is a real problem when you  
>> need
>> proxy references like MultiArray does.  The solution should be as  
>> follows:
>>
>>        for (typename Array::iterator i = x.begin(); i != x.end(); + 
>> +i) {
>>          typename Array::iterator::reference ri = *i;
>>            f(ri,v);
>>        }
>
> Ron's suggestion did fix my problem.  Thanks Ron.
>
> Just in case anyone's ever searching for a general MultiArray fill
> implementation, I've attached the now working code/test case.
>
> This might not be a bad example to add to the MultiArray tutorial,  
> both
> because it touches on an easy mistake and because people ask about
> fill with some frequency.
>
> - Rhys
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