here is my code:
#include <iostream>
class dummy{
public:
//constructor + destructor
dummy(){
std::cout<<"dummy constructed"<<std::endl;
}
//copy
dummy(const dummy& o){
std::cout<<"dummy copy init"<<std::endl;
}
void operator=(const&dummy){
std::cout<<"dummy copy operator"<<std::endl;
}
//moves
dummy(dummy&& other){
std::cout<<"dummy move init"<<std::endl;
}
void operator=(dummy&&){
std::cout<<"dummy move copy"<<std::endl;
}
};
class test{
public:
dummy d;
test(dummy&& d):d(std::move(d)){
std::cout<<"test"<<std::endl;
}
};
int main(int argc, char** argv) {
test m(dummy()); //prints NOTHING.
test t(std::move(dummy()));
return 0;
}
using test m(dummy());
Output: nothing
using test t(std::move(dummy()));
Output:
dummy constructed
dummy move init
test
Which is something that is expected.
So my question is that,
Is it mandatory to use std::move
if the parameter is type&&
?
and isn't dummy()
considered as an rvalue so why do i need to use std::move
? I am somehow confused about binding rvalues to rvalue references and i would like to need some clarification.
test m(dummy());
declares a function calledm
. You probably meant:which declares a variable
m
passing a temporarydummy
.