c++ - When to use a copy constructor? -

i have created class, has constructor takes parameter. right in thinking need copy constructor here?

i have class, not take pointers:

class xyz : public node { public:     xyz( uint8_t node);     xyz(const xyz& cxyz);     ~xyz();  private:     uint8_t m_node;     uint16_t m_gainxyz; 

and base:

class node { public:  node(); virtual ~node();  protected:     std::string  m_name; 

and when this:

xyz xyz = initxyz(node); 

the compiler tells me make copy constructor.

where:

xyz pd::initxyz(source& inputnode) {     if (inputnode.getnodenumber() > 10 )         {         xyz element(inputnode.getnodenumber());         element.setinputnode(inputnode);         return element;          }     else         {         std::cout << "error in xyz configuration" << std::endl;         //throw exception;         } } 

but according have read on web:

if object has no pointers dynamically allocated memory, shallow copy sufficient. therefore default copy constructor, default assignment operator, , default destructor ok , don't need write own.

http://www.fredosaurus.com/notes-cpp/oop-condestructors/copyconstructors.html

is true must have 1 if use constructor parameters?

i have created class, has constructor takes parameter. right in thinking need copy constructor here?

you do not need provide copy constructor classes. compiler generated ones sufficient.

here a working example based on code:

#include <iostream> #include <string> #include <stdint.h>  class node { public:    node() {}   virtual ~node() {}  protected:   std::string  m_name; };  class xyz : public node { public:     xyz( uint8_t node) {}  private:     uint8_t m_node;     uint16_t m_gainxyz; };  xyz initxyz(node) {     return xyz(42); }  int main() {     node node;     xyz xyz = initxyz(node); }