> -----Original Message-----
> From: Martin Sebor [mailto:[EMAIL PROTECTED]
> Sent: Monday, July 09, 2007 10:05 PM
> To: stdcxx-dev@incubator.apache.org
> Subject: Re: 23.deque.special
>
> > But in current implementation iterator not invalidated. Yes, it's
> > mebmers has changed, but it's still valid "end iterator".
>
> But it doesn't point to the right container. Unless I'm still
> missing something this needs to pass:
No. It point to the right container.
std::deque<int> x, y;
x._C_end._C_node always == &x._C_end._C_cur for empty container x
This condition is required by current design (include/deque, line 663)
void _C_init () {
// clear both `beg.cur' and `end.cur' and set both `beg.node'
// and `end.node' to point to `end.cur' (instead of 0) to avoid
// having to check before dereferencing the pointers
_C_beg =
_C_end = _C_deque_iter (pointer (), &_C_end._C_cur);
_C_nodes = _C_node_pointer ();
_C_node_size = 0;
}
After x.swap (y) operation x._C_end._C_node still should point to
&x._C_end._C_cur,
but not to &y._C_end._C_cur to be a valid "end iterator" of the
container x.
> > If we decide to set deque<>._C_end._C_node = 0 for end
> iterator of
> > empty deque It would be a big change (we should change the
> all places
> > where _C_end._C_node member dereferenced).
>
> Couldn't we just repoint _C_end._C_node in swap()?
http://svn.apache.org/viewvc?view=rev&revision=507940
Here I repoint _C_end._C_node to the value required by current design
after binary _STD::swap (_C_end, __rhs._C_end);
Farid.
