Re: [boost] counting_iterator<int>::difference_type

Subject: Re: [boost] counting_iterator<int>::difference_type
From: Kim Kuen Tang (kuentang_at_[hidden])
Date: 2010-04-13 05:32:36

Arno Schödl schrieb:
> Hello,
> 
>  
> 
> I am sure this has come up a few times, but I could not find the answer in the archive. 
> 
>  
> 
> counting_iterator<int>::difference_type is __int64 by default. I understand the underlying rationale, but I am not sure whether it is the right choice given the existing practice of C/C++. The problem of int minus int overflowing is not restricted to counting_iterator. Still, C/C++ chose to make int minus int -> int, probably for performance reasons. So why shouldn't counting_iterator by default behave the same way? If someone needs something else, she can still override the default.
> 
>  
You are able to override the difference_type by providing your own type. 
See:
boost::counting_iterator<int,boost::use_default,int>::difference_type

HTH

Kim
> 
> Arno
> 
> 
> --
> Dr. Arno Schoedl · aschoedl_at_[hidden] 
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>  
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