Difference between c++11 vs c++03
- by aiao
I have spend a few hours about rvalue s and lvalue. Here is what I understand
int main()
{
//.....
Foo foo = Bar1();
Foo foo = Bar2();
//......
}
Foo Bar1()
{
//Do something
return foo;
}
Foo& Bar2()
{
//Do something
return foo;
}
Under c++03, Bar1() would copy the return object (just before return), and then return the address of the copied object; executing a wasteful copy of an object which is about to be destroyed. Bar2() would return the object created within the function.
Under c++11, Bar1() and Bar2() would essentially be equivalent (and also equivalent to Bar2() of c++03).
Is that right? If not, please elaborate.
