There is a big difference between OOP and Generic Programming, Predestination.

In OOP, when you design the class, you had the interfaces you think will be useful. And it s done.

In Generic Programming, on the other hand, as long as the class conforms to a given set of requirements (mainly methods, but also inner constants or types), then it fits the bill and may be used. The Concept proposal is about formalizing this, so that detection may occur directly when checking the method signature, rather than when instantiating the method body. It also makes checking template methods more easily, since some methods can be rejected without any instantiation if the concepts do not match.

The advantage of Concepts is that you do not suffer from Predestination, you can pick a class from Library1, pick a method from Library2, and if it fits, you re gold (if it does not, you may be able to use a concept map). In OO, you are required to write a full-fledged Adapter, every time.

你是正确无误的。 差别主要在于有约束力的时间(以及概念仍然有静态的派遣,而不是像接口一样有动态的派遣)。 概念更加开放,便于使用。

Classes are a form of named conformance. You indicate that class Foo conforms with interface I by inheriting from I.

Concepts are a form of structural and/or runtime conformance. A class Foo does not need to state up front which concepts it conforms to.

The result is that named conformance reduces the ability to reuse classes in places that were not expected up front, even though they would be usable.

The concepts are in fact not part of C++, they are just concepts! In C++ there is no way to "define a concept". All you have is, templates and classes (STL being all template classes, as the name says: S tandard T emplate L ibrary).

如果你指C++0x,而不是C++(在这种情况下,我建议你改变标签),请在此读:

http://en.wikipedia.org/wiki/Concepts_(C++)

部分 我将给你写信。

In the pending C++0x revision of the C++ programming language, concepts and the related notion of axioms were a proposed extension to C++ s template system, designed to improve compiler diagnostics and to allow programmers to codify in the program some formal properties of templates that they write. Incorporating these limited formal specifications into the program (in addition to improving code clarity) can guide some compiler optimizations, and can potentially help improve program reliability through the use of formal verification tools to check that the implementation and specification actually match.

2009年7月,C++0x委员会决定从标准草案中删除概念,因为这些概念被视为C++0x的“未准备好”。

引入概念的主要动力是,以提高编造错误信息的质量。