Re: virtual destructor 101
On 19/10/2010 09:53, Dragan Milenkovic wrote:
Doesn't matter which standard. Here is on GCC-4.4
class Stack {
protected:
virtual ~Stack() = 0;
public:
virtual void foo() = 0;
};
Stack * create_stack();
void delete_stack(Stack *); // should call this one!
int main() {
Stack * stack = create_stack();
delete stack; // ERROR! virtual ~Stack is protected
}
Which is by the standard. And it works just fine to support
encapsulating memory management for Stack into factory functions.
But I still feel that this is a wrong place for making memory
management contracts.
Destructor is not memory management contract - overloaded operator new and
delete are.
Destructor belongs to object lifetime management (it's broader subject than
memory!), which I call "object ownership contract". This contract is an
important part of class' interface. If it's missused for memory management,
tough. Making up more rules won't make the language easier to master.
B.
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