Problem with Map Iterator

[Dima Sorkin]

Hi.
 There is an item exactly on this issue (deleting iterators) in
S.Meyers "Effective STL". I think there was something about incrementing
too.

Regards,
 Dima.

On 5/15/06, Peter Doerfler wrote:
>
>
> Aseem Rastogi wrote:
> > could be because when u have erased the map node pointed to by iterMap,
> > iterMap++ crashes as the memory location pointed to by iterMap becomes
> > invalid.
> >
> > so, instead of erasing in loop, do a clear () on map after the loop.
> >
>
> Alternatively, if you can't do that you can increment first and do the
> erase() then. This creates a bit of overhead and a while loop is more
> appropriate -- along these lines:
>
> while (iterMap != iterMapEnd) {
>            CS_DATAFMT* obj = iterMap->second;
>            if (obj != NULL)
>                  delete obj;
>            this->colDtlsByName.erase(iterMap++);
> }
>
> In your example, where you actually erase all nodes, the clear() method
> is more appropriate, but if you need to remove nodes conditionally, the
> above is an option.
>
> I also seem to recall reading that std::map::erase will return an
> iterator pointing to the next element in the future which would simplify
> things.... Found it: It's on the v7 branch.
>
> Best, Peter