How do I prevent a class from being allocated via the 'new' operator? (I'd like to ensure my RAII class is always allocated on the stack.)

Question

I\'d like to ensure my RAII class is always allocated on the stack.

How do I prevent a class from being allocated via the \'new\' operator?

Answer 1

I'm not convinced of your motivation.

There are good reasons to create RAII classes on the free store.

For example, I have an RAII lock class. I have a path through the code where the lock is only necessary if certain conditions hold (it's a video player, and I only need to hold the lock during my render loop if I've got a video loaded and playing; if nothing's loaded, I don't need it). The ability to create locks on the free store (with an unique_ptr) is therefore very useful; it allows me to use the same code path regardless of whether I have to take out the lock.

i.e. something like this:

unique_ptr l;
if(needs_lock)
{
    l.reset(new lock(mtx));
}
render();

If I could only create locks on the stack, I couldn't do that....