Thread: STL List Erase

Hmm. I do not generally use the STL alot, but I have a large code base that uses STL list. I was growing fond of it until....erase. Is there a way to erase an element from the list without having the list structure specifically. All I want is to be able to write:

Code:

std::list<int> foo;
foo.push_back(5);
foo.push_back(6);

std::list<int>::iterator bar;
bar = foo.begin();
bar++;

then

Code:

bar.erase();

or

Code:

erase(bar);

or some such. I have looked through the stl code and I can't find the function so its either not there or I am looking in the wrong place. Thanks for the help

http://www.dinkumware.com/manuals/de...ml#list::erase

I think you'd need to create a list that returns iterators that also contain a reference back to the list that they came from.

Originally Posted by cpjust

I think you'd need to create a list that returns iterators that also contain a reference back to the list that they came from.

You don't have to rewrite std::list, just make a new kind of iterator (based on the standard iterator).

Originally Posted by brewbuck

You don't have to rewrite std::list, just make a new kind of iterator (based on the standard iterator).

But how would you get std::list to return your custom iterator instead of its own?

I am guessing as some have mentioned I would need a custom iterator. Obviously it can't be a member function of list (unless it is a static member, which I don't think there is). It needs to be a member function of the list::iterator class. If you look at the list::erase function it is very simple I suppose I could just copy the same thing into the iterator class.

Sorry, I misread the question the first time.

I would think that remembering which list the iterator belonged to should be state added to whatever code was handling that iterator.

Creating a custom iterator or list seems like it would only make sense if you had (or expected to have) this problem in several unrelated areas of your application.