自己実現C++オブジェクトの参照数
String.h
main.cpp
#include
#include
class String {
public:
String()
: m_sp(new std::string()), m_count(new int(0)) {
*m_count = 1;
output();
std::cout << "Current function is " << __func__ << std::endl;
}
String(const std::string &s)
: m_sp(new std::string(s)), m_count(new int(0)) {
*m_count = 1;
output();
std::cout << "Current function is " << __func__ << std::endl;
}
String(const String& obj) {
m_sp = obj.m_sp;
m_count = obj.m_count;
*m_count += 1;
output();
std::cout << "Current function is " << __func__ << std::endl;
}
String &operator=(const String& rhs) {
--*m_count;
if (*m_count == 0) {
delete m_sp;
delete m_count;
}
m_sp = rhs.m_sp;
m_count = rhs.m_count;
*m_count += 1;
output();
std::cout << "Current function is " << __func__ << std::endl;
return *this;
}
~String() {
if (*m_count == 1) {
output();
std::cout << "Current function is " << __func__ << std::endl;
delete m_count;
delete m_sp;
} else {
output();
std::cout << "Current function is " << __func__ << std::endl;
--*m_count;
}
}
private:
std::string * m_sp;
int * m_count;
public:
void output() {
std::cout << "===================================================================" << std::endl;
std::cout << "The count is " << *m_count << std::endl;
}
};
main.cpp
#include
#include
#include "String.h"
int main() {
String a("abc");
String b(a);
String c("Def");
c = a;
c.output();
b.output();
return 0;
}