poly/geoobj.hpp

The following code example is taken from the book
C++ Move Semantics - The Complete Guide by Nicolai M. Josuttis, Leanpub, 2020
The code is licensed under a Creative Commons Attribution 4.0 International License.

---

// raw code

#ifndef GEOOBJ_HPP
#define GEOOBJ_HPP

#include "coord.hpp"
#include <string>

class GeoObj {
protected:
  std::string name;                 // name of the geometric object

  GeoObj(std::string n)
   : name{std::move(n)} {
  }  
public:
  std::string getName() const {
    return name;
  }

  virtual void draw() const = 0;    // pure virtual function (introducing the API)

  virtual ~GeoObj() = default;      // would disable move semantics for name
protected:
  // enable copy and move semantics (callable only for derived classes):
  GeoObj(const GeoObj&) = default;
  GeoObj(GeoObj&&) = default;
  // disable assignment operator (due to the problem of slicing):
  GeoObj& operator= (GeoObj&&) = delete;
  GeoObj& operator= (const GeoObj&) = delete;
  //...
};

#endif // GEOOBJ_HPP