Re: static_cast and dynamic_cast
On 11 Oct, 16:51, MC <manan.cho...@gmail.com> wrote:
#include <iostream>
using namespace std;
class X{
public:
virtual void f(){}
};
class Y {
public:
virtual void g() {}
};
int main()
{
X * x = new X();
Y* y = dynamic_cast<Y*>(x); //A
// Y* y = static_cast<Y*>(x); //B
cout << y << endl;
}
When I try to typecast an unrelated class(not in its inheritance
hierarchy) into another as in the above example,
using a static_cast (line B) I get a compile time error. Whereas with
dynamic_cast the code compiles just fine.
I am curious why doesn't the compiler give a compile type error also
in the case of dynamic_cast?
Because it has a well defined result - (Y*)0 and you could probably
find cases where this would be useful in template code even if just
seems stupid in your simple example
--
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