Why STL containers are preferred over MFC containers?

Question

Previously, I used to use MFC collection classes such CArray and CMap. After a while I switched to STL containers and have been using them for a while.

Answer 1

It is now assumed that C++ developers are at least passingly familiar with the STL. Not so for MFC containers. So if you're adding a new developer to your team, you will have an easier time finding one who know STL than the MFC containers, and thus will be able to contribute immediately.

Answer 2

Because a library that uses iterators to combine sequences of any kind with algorithms so that A) all sensible permutations are possible and B) it's universally extensible, is (when you think about your concept of a container library as it was 15 years ago) such a mind-blowingly marvelous idea, that it has pretty much blown out of the water everything else within less than a decade?

Seriously, the STL has its flaws (why not ranges instead of iterators? and that erase-remove idiom is not exactly pretty), but it's based on a brilliant idea and there's very good reasons we don't need to learn a new container/algorithms library every time we start at a new job.

Answer 3

• STL has more collection types than MFC
• Visual Studio (2008+) debugger visualizes STL much better than MFC. (AUTOEXP.DAT magic can fix that - but it is a pain! Nothing like debugging your debugger when you screw it up...)

One good thing with MFC is that there is still a large corpus of MFC code out there. Other answers talk about third-party compatibility. Don't forget third party MFC-based stuff.

Answer 4

I always prefer using more standard/compatible libraries where I can since I may have future projects that I can reuse a portion of the code on. I have no idea what libraries future projects will use, but I have a better chance of making my code reusable if I use standard/compatible stuff.

Also, the more I use a library, I get more comfortable and quicker with it. If I am going to invest the time to learn a library, I want to make sure it's going to stay around and is not tied in with a specific platform or framework.

Of course, I say all of this assuming that my choices are rather similar when it comes to performance, features and ease of use. For instance, if the MFC classes are a significant enough improvement in these areas, I would use them instead.

Answer 5

I wouldn't totally dismiss the portability argument. Just because you use MFC today doesn't mean that you always will. And even if you mostly write for MFC, some of your code could be re-used in other applications if it were more generic and standards-based.

I think the other reason to consider STL is that its design and evolution has benefited from libraries that have come before, include MFC and ATL. So many of the solutions are cleaner, more re-usable, and less error prone. (Though I wish they had a better naming convention.)

Answer 6

I think it boils down to a simple question: Who do you trust more? If you trust Microsoft, then continue to use the MFC variants. If you trust the industry, then use STL.

I vote for STL because the code that runs on Windows today might need to be ported to another platform tomorrow. :)