Bjarne: That depends on what you mean by “C++ 2.0.” If you mean a new language built more or less from scratch providing all of the best of C++ but none of what’s bad (for some definitions of “good” and “bad”), the answer is “I don’t know.” I would like to see a major new language in the C++ tradition, but I don’t see one on the horizon, so let me concentrate on the next ISO C++ standard, nicknamed C++0x.
It will be a “C++ 2.0” to many, because it will supply new language features and new standard libraries, but it will be almost 100% compatible with C++98. We call it C++0x, hoping that it’ll become C++09. If we are slow—so that that x has to become hexadecimal—I (and others) will be quite sad and embarrassed.
C++0x will be almost 100% compatible with C++98. We have no particular desire to break your code. The most significant incompatibilities come from the use of a few new keywords, such as static_assert, constexpr, and concept. We have tried to minimize impact by choosing new keywords that are not heavily used. The major improvements are:
• Support for modern machine architectures and concurrency: a machine model, a thread library, thread local storage and atomic operations, and an asynchronous value return mechanism (“futures”).
• Better support for generic programming: concepts (a type system for types, combinations of types, and combinations of types and integers) to give better checking of template definitions and uses, and better overloading of templates. Type deduction based on initializers (auto), generalized initializer lists, generalized constant expressions (constexpr), lambda expressions, and more.
• Many “minor” language extensions, such as static assertions, move semantics, improved enumerations, a name for the null pointer (nullptr), etc.
• New standard libraries for regular expression matching, hash tables (e.g., unordered_map), “smart” pointers, etc.
Please note that when I talk about “not breaking code,” I am referring to the core language and the standard library. Old code will of course be broken if it uses nonstandard extensions from some compiler provider or antique nonstandard libraries. In my experience, when people complain about “broken code” or “instability” they are referring to proprietary features and libraries. For example, if you change operating systems and didn’t use one of the portable GUI libraries, you probably have some work to do on the user interface code.
Source of Information : Oreilly - Masterminds of Programming
It will be a “C++ 2.0” to many, because it will supply new language features and new standard libraries, but it will be almost 100% compatible with C++98. We call it C++0x, hoping that it’ll become C++09. If we are slow—so that that x has to become hexadecimal—I (and others) will be quite sad and embarrassed.
C++0x will be almost 100% compatible with C++98. We have no particular desire to break your code. The most significant incompatibilities come from the use of a few new keywords, such as static_assert, constexpr, and concept. We have tried to minimize impact by choosing new keywords that are not heavily used. The major improvements are:
• Support for modern machine architectures and concurrency: a machine model, a thread library, thread local storage and atomic operations, and an asynchronous value return mechanism (“futures”).
• Better support for generic programming: concepts (a type system for types, combinations of types, and combinations of types and integers) to give better checking of template definitions and uses, and better overloading of templates. Type deduction based on initializers (auto), generalized initializer lists, generalized constant expressions (constexpr), lambda expressions, and more.
• Many “minor” language extensions, such as static assertions, move semantics, improved enumerations, a name for the null pointer (nullptr), etc.
• New standard libraries for regular expression matching, hash tables (e.g., unordered_map), “smart” pointers, etc.
Please note that when I talk about “not breaking code,” I am referring to the core language and the standard library. Old code will of course be broken if it uses nonstandard extensions from some compiler provider or antique nonstandard libraries. In my experience, when people complain about “broken code” or “instability” they are referring to proprietary features and libraries. For example, if you change operating systems and didn’t use one of the portable GUI libraries, you probably have some work to do on the user interface code.
Source of Information : Oreilly - Masterminds of Programming
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