I have the following imbecile program:
#include <iostream>
using namespace std;
class Baz {
public:
Baz() {cout << "Baz ctor " << endl;}
Baz(int i) : Baz() {}
~Baz() {cout << "Baz dtor " << endl;}
};
int main()
{
cout << "w" << endl;
Baz w;
cout << "x" << endl;
Baz x();
cout << "y" << endl;
Baz y(1);
cout << "z" << endl;
Baz z = Baz();
return 0;
}
This produces the following output:
w
Baz ctor
x
y
Baz ctor
z
Baz ctor
Baz dtor
Baz dtor
Baz dtor
My question is thus: Why don't all these calls invoke the constructor?
I have been researching, but I have not found an explanation as to why the 2nd call does not invoke the constructor. I would expect Baz x()
to be equivalent to Baz x = Baz()
the same way that Baz y(1)
would be equivalent to Baz y = Baz(1)
, there must be something I'm missing.
Your statement Baz x();
declares x
as a function with no parameters that returns a Baz
. Change it to Baz x{};
or Baz x;
to call the default constructor.
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