编程语言提供的抽象关键字

Different programming languages provide different types of abstraction, depending on the intended applications for the language. For example:

• In object-oriented programming languages such as C++, Object Pascal, or Java, the concept of abstraction has itself become a declarative statement – using the keywords virtual (in C++) or abstract^[11] and interface^[12] (in Java). After such a declaration, it is the responsibility of the programmer to implement a class to instantiate the object of the declaration.
• Functional programming languages commonly exhibit abstractions related to functions, such as lambda abstractions (making a term into a function of some variable) and higher-order functions (parameters are functions).

 

https://en.wikipedia.org/wiki/Abstraction_(computer_science)