相关疑难解决方法(0)

在类的赋值运算符中,通常需要检查所分配的对象是否是调用对象,这样就不会搞砸了:

Class& Class::operator=(const Class& rhs) {
    if (this != &rhs) {
        // do the assignment
    }

    return *this;
}

移动赋值运算符需要相同的东西吗？是否有过这样的情况this == &rhs？

? Class::operator=(Class&& rhs) {
    ?
}

参考http://en.wikipedia.org/wiki/Copy_elision

我运行下面的代码:

#include <iostream>

struct C {
  C() {}
  C(const C&) { std::cout << "Hello World!\n"; }
};

void f() {
  C c;
  throw c; // copying the named object c into the exception object.
}          // It is unclear whether this copy may be elided.

int main() {
  try {
    f();
  }
  catch(C c) {  // copying the exception object into the temporary in the exception declaration.
  }             // It is also unclear whether this copy may be …