Declare abstract class in c

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What is the best way to declare an abstract class?

For instance, I'm aware that it employs the term "virtual," as in:

class test{
public:
virtual void test()=0;
}

My question is can I abstract test class like this? If not why and how

virtual class test{
}

May 28, 2022 in C++ by Nicholas
• 7,760 points
553 views

1 answer to this question.

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An abstract class is one that is intended to be used as a base class . 

At least one pure virtual function exists in an abstract class. 

A pure virtual function is declared in the class declaration by using a pure specifier (= 0) in the declaration of a virtual member function.

Here is an example of an abstract class:

class AB { public: virtual void f() = 0; };

The AB::f function is a pure virtual function. 

There can't be a pure specifier and a definition in the same function declaration. 

The compiler, for example, will not permit the following:

struct A { virtual void g() { } = 0; };
answered May 31, 2022 by Damon
• 4,960 points

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