A C++ derivative that is backwards-compatible with older C/C++ code?

Does such a language exist?

There are a few qualms in C++ that could be fixed with a derivative that 开发者_开发问答is backwards-compatible.

C++0x will be compatible with both older C and older C++.

Are you asking if there is a new language, or something similar to C++ that maintains backwards compatibility? For example, are you looking for something like C# that also supports C/C++ syntax? If so, you might want to look at "Managed C++", which turns C++ into a language that runs on the CLR. By running on the CLR, it can interact with other languages such as C#. However, there are some things with managed C++ that might not make it an ideal language to work with. (Such as a few new keywords)

If you're talking about the "soon to be released" C++ (known as C++0x), it is supposed to maintain compatibility with older C++ code. It should be very compatible with C language features, too. (If you're talking about older C/C++ code being code developed in the mid to late 1990s, which uses C++ features like objects, static_casts and inheritance, but doesn't use items from the STL, it should be near 100% compatible)

There are quite a few extensions of C++. For one, there's Blocks which are used in OSX 10.6's Grand Central Dispatch thread system. There's also C++0x, which is the name for the next update of the C++ standard. Many compilers also have their own extensions. Here are GCC's c++ extensions. C++ it's self is almost an extension of C. C code can usually be compiled with a C++ compiler with only a few changes, and C libraries can be used in C++.

I doubt that there are any alternative languages that are 100% (or even 90%) compatible with existing C++ code. C++ is one of the most-complex programming languages ever, so building a new language on top of that would tend to lead to a very complex language.

Edited

Managed C++ and C++.NET is compatible with older C and C++. I dont know how compatible it is.