Strange std::list error

The error means what it says. _Ptr is a private member of the iterator (not irritator [grin]), you simply want to dereference the iterator.

if (it->MyVal == SomeVar){  // Do work}

Quote:

Original post by Magister why is that ?

One of the golden rules in C++ programming is that identifiers which start with an underscore followed by a capital letter are reserved and should not be used, lest unusual and mildly uncomfortable things happen to you.

You used _Ptr, which was public in debug and private in release, so it stopped working. The solution is simple: don't use _Ptr. List iterators provide overloaded operator* and operator->, use these.

1) It's called an iterator.
2) Whatever you did to find out that there is such a thing as '_Ptr' is something you should not be doing. (Or at least, you should only be doing so with the discipline to ignore what you find out. [wink]) Keep in mind that it's only necessarily present in the standard library implementation that you are using.
3) Switching to is, by itself, not fixing your problem, in any way, shape or form.. Switching to "so that you can use raw pointers instead of iterators" is (a) almost certainly shooting yourself in the foot and (b) losing flexibility for, probably, no performance benefit.

You know how those OO advocates are always trying to tell you something about "interface vs. implementation"? This would be one of those issues. The standard library's interface is well known. In particular, all iterator objects provide the interface "behave just like a pointer in every way that makes sense, except that sequential values correspond to elements of the container, rather than memory addresses". The implementation - who knows? The whole point is you don't have to know, and you are wasting your time trying to find out. By not knowing, you enable your compiler vendor to improve things "under the hood" while guaranteeing that your code will still work, without changing a thing.