Thread: simple scope question

Hey, would you mind offering your clarification here for me.

Not being familiar with object factories, I can only offer speculation, and it'll be based on the definition of object factory here (even though it's from Java):
http://java.sun.com/products/jndi/tu...jects/factory/

So my guess is, an object factory works something like this:

Code:

SomeObject createObject(int arg1, int arg2, double arg3)
{
   return SomeObject(arg1, arg2, arg3, someDataOnlyThisFunctionCanAccess);
}

...

SomeObject s = createObject(1, 2, 3.4);

So what happens is, a SomeObject object is constructed using the data provided, and this object is returned - i.e. a copy of it is made, and then s is constructed by some method that involves the returned copy - and then the return statement ends, and this temporarily constructed SomeObject object goes out of scope and is destroyed, and the copy that s was constructed from also goes out of scope and is destroyed. But s has already been constructed/copied in some sequence from the originally created object, and therefore since it is a copy and not a pointer to the original, it is not destroyed.

Alternately, the object factory might return a pointer to a dynamically created object (i.e. created using new), and therefore the object never goes out of scope and must be deleteed manually.

>>as long as there was a viable pointer to a memory location than the object persisted
You can emulate this using smart pointers that implement reference-counting (take a look here for an example of how it can be done manually), but it is by no means automatically done for you. As far as I know, COM uses reference counting, and if you forget to free a resource then the reference count never reaches 0 and the resource is never destroyed as it should be.

Ahh I see. Thankyou Hunter2 and skorman00; that was very enlightening.