I have a URes class which contains a single pointer to <T>, with indirection operators -> and * overloaded so I can use the instance as a pointer directly.
However I also want to be able to pass my URes instance to functions that normally take the pointer inside the URes instance.
How do I make it so that when my URes instance object is passed to a function it is automatically cast to the pointer it contains?
The same way that you create any outbound conversion: by declaring and defining an operator.
In this case, you want a member operator T*.
template <typename T>
struct Foo {
operator T*() {
return 0;
}
};
void bar(int* p) {}
int main() {
Foo<int> f;
bar(f);
}
However, I'd recommend avoiding this and implementing a member T* get() instead. It should be an explicit step for a calling scope to obtain a pointer from your object.
You can do that by providing a conversion operator from that class to the pointer-type:
class Foo {
public:
operator int() const { // enables implicit conversion from Foo to int
}
};
Note that such implicit conversion can introduce unexpected behavior.
