copy-constructor

This is homework I'm working on implementing a linked list class for my C++ class, and the copy constructor has be very confusing for me. The linked list is comprised of structs called Elems: struct Elem { int pri; data info; Elem * next; }; Elem * head; info is a separate, custom class that is stored in the Elem. the signature for the copy constructor is: linkedList::linkedList( const linkedList &v ) The issue I am having is mostly taking my logic and actually writing it as code. My general idea is to: Set head to v.head (head = v.head) Set the Elem's values to v's (pri = v.pri , info = v

Are variadic constructors supposed to hide the implicitly generated ones, i.e. the default constructor and the copy constructor? struct Foo { template<typename... Args> Foo(Args&&... x) { std::cout << "inside the variadic constructor\n"; } }; int main() { Foo a; Foo b(a); } Somehow I was expecting this to print nothing after reading this answer , but it prints inside the variadic constructor twice on g++ 4.5.0 :( Is this behavior correct? It also happens without variadic templates: struct Foo { Foo() { std::cout << "inside the nullary constructor\n"; } template<typename A> Foo(A&& x) { std:

For one reason or another, I'm forced to provide both a copy constructor and an operator= for my class. I thought I didn't need operator= if I defined a copy ctor, but QList wants one. Putting that aside, I hate code duplication, so is there anything wrong with doing it this way? Fixture::Fixture(const Fixture& f) { *this = f; } Fixture& Fixture::operator=(const Fixture& f) { m_shape = f.m_shape; m_friction = f.m_friction; m_restitution = f.m_restitution; m_density = f.m_density; m_isSensor = f.m_isSensor; return *this; } And just out of curiosity, there's no way to switch it so that the bulk

I understand copy constructor is called on three instances When instantiating one object and initializing it with values from another object. When passing an object by value. 3. When an object is returned from a function by value. I have question with no.3 if copy constructor is called when an object value is returned, shouldn't it create problems if object is declared locally in the function. i mean the copy constructor is a deep copy one and takes reference of an object as parameter It's called exactly to avoid problems. A new object serving as result is initialized from the locally-defined

I wrote the following program to test when the copy constructor is called and when the assignment operator is called: #include class Test { public: Test() : iItem (0) { std::cout << "This is the default ctor" << std::endl; } Test (const Test& t) : iItem (t.iItem) { std::cout << "This is the copy ctor" << std::endl; } ~Test() { std::cout << "This is the dtor" << std::endl; } const Test& operator=(const Test& t) { iItem = t.iItem; std::cout << "This is the assignment operator" << std::endl; return *this; } private: int iItem; }; int main() { { Test t1; Test t2 = t1; } { Test t1; Test t2 (t1); }