Error No Matching Function For Call To Copy Constructor
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Error No Matching Function For Call To 'strlen'
Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads error no matching function for call to 'strtok' 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, error no matching function for call to 'atoi' just like you, helping each other. Join them; it only takes a minute: Sign up error: no matching function for call to default copy constructor? up vote 1 down vote favorite 1 I have a std::map container variable in my class that is populated with objects of my nested-class: class Logger { private: //... class
Error No Matching Function For Call To ‘find
Tick{ ///stores start and end of profiling uint32_t start, lastTick,total; /// used for total time boost::mutex mutexTotalTime; ///is the profiling object started profiling? bool started; public: Tick(){ begin(); } /* Tick(const Tick &t){ start = t.start; lastTick = t.lastTick; total = t.total; started = t.started; } */ uint32_t begin(); uint32_t end(); uint32_t tick(bool addToTotalTime = false); uint32_t addUp(uint32_t value); uint32_t getAddUp(); }; std::map
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Error No Matching Function For Call To 'forward'
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 http://stackoverflow.com/questions/25359302/error-no-matching-function-for-call-to-default-copy-constructor takes a minute: Sign up Copy constructor related compiler error up vote 3 down vote favorite I have a resource that is shared between two concurrent threads. The resource contains a vector that both threads need to read and write to. Hence, I make access to the vector exclusive through a mutex. So far so good, sharing of resource works well http://stackoverflow.com/questions/26921534/copy-constructor-related-compiler-error without any problems. However, the problem starts when I try to write a copy constructor for sharedResource as follows. class sharedResource{ public: sharedResource(){} sharedResource(const sharedResource &other) { vec = other.GetVec(); } std::vector
are special member functions used when an object is "constructed" (created). They have the same name as the class. The following code creates a class called A, then an object of that type. class A { public: int i; }; int main() { A a; http://www-h.eng.cam.ac.uk/help/tpl/languages/C++/constructors.html } There's no explicit function called A - when a is created, a constructor is https://gcc.gnu.org/ml/gcc/2005-05/msg00896.html used that the compiler has created. This time we'll create a constructor that, given an integer, sets the member variable i to that value. class A { public: int i; A(int x) { i=x;}; }; int main() { A a; } Though we don't use that constructor, the code doesn't compile, because as soon as you start writing your error no own constructors, none of the default constructors are created. The error message will be something like // error: no matching function for call to A::A() // note: candidates are: A::A(int) // note: A::A(const A&) (more about that final line later) In the following, a default value is defined for the constructor argument (i.e. if no value is supplied, 7 is used). Now compilation works. class A { public: int i; A(int x=7) { i=x;}; error no matching }; int main() { A a; } In the next example an argument is given when an object of type A is created, so that's ok too. class A { public: int i; A(int x) { i=x;}; }; int main() { A a(1); } The next example has an explicit constructor for when no parameter is given, and another constructor for when a single integer parameter is given. The programmer's trying to create a with one parameter, and b using no parameters. class A { public: int i; A() {}; A(int x) { i=x;}; }; int main() { A a(1); A b(); } The code compiles, but doesn't do what the programmer intended. Adding b.i=0; exposes the problem - there's a compilation error. To run the constructor with no parameters, A b; is needed. A b(); is a prototype for a function b that returns an object of type A. Copy constructor There's another type of constructor - it's called a copy constructor. It's used when an object is created by a copy being taken of an existing variable. class A { public: int i; A(const A&){}; // Copy constructor }; int main() { A a; A b=a; } But the code doesn't compile - copying works, but a itself isn't created. Again, because we're created a constructor, no default construct
"No matching function" -- not finding copy constructor From: Joe Buck