Re: [boost] [ptr_container] iterators bug

From: Alexey Bakhvalov (bakhvalov_at_[hidden])
Date: 2005-06-14 18:18:10

"Thorsten Ottosen" <nesotto_at_[hidden]> wrote in message
news:d8nb2d$92j$1_at_sea.gmane.org...
> "Alexey Bakhvalov" <bakhvalov_at_[hidden]> wrote in message
> news:d8l314$p0h$1_at_sea.gmane.org...
> | Btw, I get similar error if I try to subtract iterator from
> const_iterator
> | (or vice versa).
> | Example:
> |
> | typedef boost::ptr_vector<char> TContainer;
> | TContainer some_vector;
> | TContainer::const_iterator it1 = some_vector.begin();
> | TContainer::iterator it2 = some_vector.begin();
> | size_t diff = it1 - it2;
> |
> | It seems that there is a problem with all binary operators that take
> | iterators as operands.
>
> ah yes. I haven't got time to look in the standard, but must iterator and
> const_iterator be
> completely interchangable?
>

I can't find anything in the standard that would explicitly state this but I 
thought that random iterators should mimic regular pointers in as many ways 
as possible (and language allows such operations on pointers).
It would be good if someone else could comment on this issue.