I am trying to understand the details of boost function. Below is the
sample code that I am using. I was expecting the copy constructor to be
invoked once. However, I see that it is called four times. I am trying
to understand why does boost function need to have four copies of my
objects. I am using boost version 1_33_1.
Any thoughts/comments..
#include <iostream>
#include
#include
#include "boost/function.hpp"
#include <map>
using namespace std;
class F
{
public:
F() {
cout << "Cons" << endl;
}
F(const F&) {
cout << "Copy const" << endl;
}
F& operator=(const F&) {
cout << "operator = " << endl;
return *this;
}
int operator()(int a, int b) { cout <<" Sub" << endl; return a - b;
}
};
int main() {
FUNC f = F();
}
Output:
Cons
Copy const
Copy const
Copy const
Copy const
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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