Error Definition Of Implicitly-declared Destructor
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here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about error definition of implicitly declared copy constructor Stack Overflow the company Business Learn more about hiring developers or posting ads with error definition of implicitly declared default constructor us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is definition of implicitly declared c++ a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Destructor of a class implicitly defined up vote 1 down vote favorite 1 Consider definition of implicitly declared copy assignment operator the case of class which does not have a destructor and constructor explicitly declared by the developer. I understand that a destructor for a class will be implicitly declared in this case. Then is it true that the destructor is implicitly defined, only when an object of the class is about to be destroyed? Is the behavior of constructor also the same as above. Is it implicitly defined only when
Error Definition Of Implicitly-declared C++
an object of the class is created? EDIT class A { public: }; int main() { } In the above code, ~A() will be implicitly declared. My question is whether it true that the definition for the destructor will be made implicitly, only if an object of the class is instantiated like class A { public: }; int main() { A a; } Or is it implicitly defined, even if object instantiation is not done ? c++ constructor destructor explicit-constructor share|improve this question edited Dec 19 '11 at 15:12 asked Dec 19 '11 at 14:57 nitin_cherian 2,130134388 Maybe we can give better answers if you explain why this is relevant. –Sebastian Mach Dec 19 '11 at 15:03 Are you making some sort of distinction between implicitly declared and implicitly defined? I am really struggling to understand the question... –NPE Dec 19 '11 at 15:05 I have added some code snippet for clarity. –nitin_cherian Dec 19 '11 at 15:13 @LinuxPenseur: What do you need this for? –Sebastian Mach Dec 19 '11 at 15:24 @phresnel : I am studying the basics of the C++ language. I want a concrete idea of what is happening. If ever someone asks me the question
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Definition Of Implicitly-declared Operator=
Us Learn more about Stack Overflow the company Business Learn more about hiring definition of implicitly-declared ‘virtual developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the which is of non-class type Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Can anyone help me understand this http://stackoverflow.com/questions/8563116/destructor-of-a-class-implicitly-defined error? “definition of implicitly-declared ‘classA::classA()’” up vote 20 down vote favorite 1 Heres the code: #include
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads http://stackoverflow.com/questions/8563116/destructor-of-a-class-implicitly-defined with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: http://en.cppreference.com/w/cpp/language/destructor Sign up Destructor of a class implicitly defined up vote 1 down vote favorite 1 Consider the case of class which does not have a destructor and constructor explicitly declared by the developer. I understand that a destructor for a class will definition of be implicitly declared in this case. Then is it true that the destructor is implicitly defined, only when an object of the class is about to be destroyed? Is the behavior of constructor also the same as above. Is it implicitly defined only when an object of the class is created? EDIT class A { public: }; int main() { } In the above code, ~A() will be implicitly declared. My question is whether it true that the definition for the destructor will definition of implicitly be made implicitly, only if an object of the class is instantiated like class A { public: }; int main() { A a; } Or is it implicitly defined, even if object instantiation is not done ? c++ constructor destructor explicit-constructor share|improve this question edited Dec 19 '11 at 15:12 asked Dec 19 '11 at 14:57 nitin_cherian 2,130134388 Maybe we can give better answers if you explain why this is relevant. –Sebastian Mach Dec 19 '11 at 15:03 Are you making some sort of distinction between implicitly declared and implicitly defined? I am really struggling to understand the question... –NPE Dec 19 '11 at 15:05 I have added some code snippet for clarity. –nitin_cherian Dec 19 '11 at 15:13 @LinuxPenseur: What do you need this for? –Sebastian Mach Dec 19 '11 at 15:24 @phresnel : I am studying the basics of the C++ language. I want a concrete idea of what is happening. If ever someone asks me the question after i have mastered the language, i should be able to give the correct answer. –nitin_cherian Dec 19 '11 at 15:34 | show 1 more comment 3 Answers 3 active oldest votes up vote 4 down vote accepted Yes, implicitly declared default constructors and destructors are implicitly defined when they are used to create or destroy instances of the object. In the words of the standard (C++11): 12.1/6: A default constructor that is defaulted and not defi
library Containers library Algorithms library Iterators library Numerics library Input/output library Localizations library Regular expressions library (C++11) Atomic operations library (C++11) Thread support library (C++11) Filesystem library (C++17) Technical Specifications [edit] C++ language Classes General overview class/struct types union types Members data members static members the this pointer nested classes member templates bit fields using-declarations member functions member access specifiers constructors and member initializer lists default member initializer(C++11) friend specifier explicit specifier converting constructor Special member functions default constructor copy constructor move constructor(C++11) copy assignment operator move assignment operator(C++11) destructor Inheritance base and derived classes virtual member functions override(C++11) final(C++11) pure virtual functions and abstract classes [edit] A destructor is a special member function that is called when the lifetime of an object ends. The purpose of the destructor is to free the resources that the object may have acquired during its lifetime. Contents 1 Syntax 2 Explanation 3 Implicitly-declared destructor 4 Deleted implicitly-declared destructor 5 Trivial destructor 6 Implicitly-defined destructor 7 Destruction sequence 8 Virtual destructors 9 Pure virtual destructors 10 Exceptions 11 Example [edit] Syntax ~ class_name (); (1) virtual ~ class_name (); (2) decl-specifier-seq(optional) ~ class_name () = default; (3) (since C++11) decl-specifier-seq(optional) ~ class_name () = delete; (4) (since C++11) attr(optional) decl-specifier-seq(optional) id-expression ( void(optional) ) except(optional) attr(optional) ; (5) 1) Typical declaration of a destructor 2) Virtual destructor is usually required in a base class 3) Forcing a destructor to be generated by the compiler 4) Disabling the implicit destructor 5) Formal syntax of a destructor declaration decl-specifier-seq - friend, inline, virtual, or nothing (no return type) id-expression - within a class definition, the symbol ~ followed by the class name. Within a class template, the symbol ~ followed by the name of the current instantiation of the template. At namespace scope or in a friend declaration within a different class, nested-name-specifier fol