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No, inlining is done at compile time whereas virtual functions are resolved at run time(late binding). So, virtual functions can't be inlined. Both properties are orthogonal.Inlining is a mere suggestion the compiler may ignore it if it is declared with virtual function.
Wiki User
∙ 12y ago
Wiki User
∙ 10y agoYes. Any non-derived class that declares at least one virtual function must also have a virtual destructor. It makes no difference if the virtual function is pure-virtual or just virtual; without a virtual destructor, derived classes cannot be destroyed when base classes fall from scope. However, once a destructor is declared virtual, all derived destructors are effectively virtual through implication (the virtual keyword is optional when overriding an inherited virtual interface).
The only major difference between a pure-virtual function and virtual function is that a pure-virtual function will render your class abstract. A generic implementation for a pure-virtual function is entirely optional, but derived classes cannot inherit that implementation (although they can explicitly call it) and they must provide an implementation for that function (or it will be rendered abstract as well). Once a derived class implements a pure-virtual function, that function is effectively rendered virtual and can then be inherited by subsequent derivatives (access permitting). However, only classes that either provide or inherit a complete implementation for all pure-virtual methods can be physically instantiated.
When you declare a virtual function, you must provide a generic implementation, but it need not be overridden by a derivative if the generic implementation suffices for that derivative.
Ultimately, any class may have any combination of non-virtual, virtual and pure-virtual functions. The purpose of the class will ultimately determine which combination you need.
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Do you use virtual functions in Java?
Every method in java that isn't a class (static) method is automatically "virtual." If you want to disable virtual overrides, make the method "final" in the base class.
How does virtual function support run time polymorphism?
Virtual functions are used to suport runtime polymorphism.In C++,if we have inheritance and we have overridden functions in the inherited classes,we can declare a base class pointer and make it to point to the objects of derived classes.When we give a keyword virtual to the base class functions,the compiler will no do static binding,so during runtime ,the base class pointer can be used to call the functions of the derived classes.Thus virtual functions support dynamic polymorphism.
What is the difference between virtual function and function overriding?
Virtual Functions and Pure Virtual Functions are relevant in the context of class inheritance.Unlike Virtual Functions, Pure Virtual Functions do not require a body. This implies that when a base class defining such a function is inherited, the derived class must implement that function. Furthermore, the base class becomes abstract; meaning you cannot create an instance of the base class even if a body is implemented for the function. You are expected to derive from abstract classes; only the derived classes that implement all the inherited Pure Virtual functions can be instantiated.Here are some examples of Virtual and Pure Virtual function signatures:- Virtual Function: E.g. virtual void myFunction();- Pure Virtual Function: E.g. virtual void myFunction() = 0;
What is a pure virtual member function in c plus plus?
Functions in C++ are separate procedures or subroutines within a program, that can be called as often as required and which can return values back to their callers. That is, when you make a function call, execution passes to the function and then returns to the caller. Functions that are class members are also known as member functions, member methods, or simply methods. These work exactly the same as external functions except they are scoped to the class and have access to private members of the class.
How do you represent a C plus plus non-pure virtual function in UML?
All virtual functions (including pure-virtual functions) are represented in italics. All non-virtual functions are represented normally. There is no differentiation between pure and non-pure virtual functions, however some people append "=0" to distinguish the pure-virtual functions.
Why inline functions shall not be defined with extern or static storage class?
inline itself should be considered as a storage class
How do virtual functions differ from pure virtual functions?
Virtual functions is a function that can be overridden in inheriting class with the same signature (function name, parameters number, parameters types and return type);Pure virtual function is function that does not have implementation and if class has pure virtual function is called abstract. It is not possible to instantiate that class. Some other class must inherit it and define the body for it (implement). In other words class only have function prototype/declaration(signature) and no definition(implementation).
Do you use virtual functions in Java?
Every method in java that isn't a class (static) method is automatically "virtual." If you want to disable virtual overrides, make the method "final" in the base class.
What are the disadvantages of inline functions?
The inline functions is an optimization technique that is used by the compilers. The disadvantage of the inline functions is the increased binary size.
How does virtual function support run time polymorphism?
Virtual functions are used to suport runtime polymorphism.In C++,if we have inheritance and we have overridden functions in the inherited classes,we can declare a base class pointer and make it to point to the objects of derived classes.When we give a keyword virtual to the base class functions,the compiler will no do static binding,so during runtime ,the base class pointer can be used to call the functions of the derived classes.Thus virtual functions support dynamic polymorphism.
What is the difference between virtual function and function overriding?
Virtual Functions and Pure Virtual Functions are relevant in the context of class inheritance.Unlike Virtual Functions, Pure Virtual Functions do not require a body. This implies that when a base class defining such a function is inherited, the derived class must implement that function. Furthermore, the base class becomes abstract; meaning you cannot create an instance of the base class even if a body is implemented for the function. You are expected to derive from abstract classes; only the derived classes that implement all the inherited Pure Virtual functions can be instantiated.Here are some examples of Virtual and Pure Virtual function signatures:- Virtual Function: E.g. virtual void myFunction();- Pure Virtual Function: E.g. virtual void myFunction() = 0;
What is a pure virtual member function in c plus plus?
Functions in C++ are separate procedures or subroutines within a program, that can be called as often as required and which can return values back to their callers. That is, when you make a function call, execution passes to the function and then returns to the caller. Functions that are class members are also known as member functions, member methods, or simply methods. These work exactly the same as external functions except they are scoped to the class and have access to private members of the class.
Is inline function a command?
No, functions (inline or other) aren't commands.
How do you represent a C plus plus non-pure virtual function in UML?
All virtual functions (including pure-virtual functions) are represented in italics. All non-virtual functions are represented normally. There is no differentiation between pure and non-pure virtual functions, however some people append "=0" to distinguish the pure-virtual functions.
What is the difference between inline and const?
Everything. "inline" refers to functions, "const" refers to variables.
When will you make inline function?
Trivial functions, such as member variable accessors that simply return a member's value, are prime candidates for inline expansion. However trivial non-member functions can also be inline expanded, as can any non-trivial function that is rarely called.Member functions defined in the body of the class declaration are implicitly declared inline. However, whether a function is explicitly declared inline or not, the compiler is free to ignore any inline request, such as when the inline expansion of a non-trivial function would adversely compromise code size, for instance.Note that inline expansion replaces the call to a function with a modified version of the function's body within the calling functions -- just as if you'd duplicated the code yourself, rather than creating a separate function -- which removes the overhead of making a function call.The only way to force a function inline is to manually write the expanded code yourself. But if the code appears in several places, maintenance of the code will be compromised.If there's ever any doubt, declare it inline and let the compiler decide. It's in a far better position to determine if it should be inline expanded or not.
When do we make a virtual function pure?
We make a virtual function pure whenever we wish to make our class an abstract base class (an abstract data type). Unlike a virtual function, pure virtual functions must be overridden by a derived class or by one of its derivatives (the function remains pure virtual until it is overridden, at which point it becomes virtual). Derived classes that do not provide a complete implementation for all the pure virtual functions it inherits become abstract themselves. You cannot instantiate an abstract base class other than through derivation.
