AS3 Memory management when instantiating extended classes

Question

I'm developing an AS3 application which has some memory leaks I can't find, so I'd like to ask some newbie questions about memory management.

Imagine I have a class named BaseClass, and some classes that extend this one, such as ClassA, ClassB, etc.

I declare a variable:

myBaseClass:BaseClass = new ClassA();

After a while, I use it to instantiate a new object:

myBaseClass = new ClassB(); 

some time after

myBaseClass = new ClassC(); 

and the same thing keeps happening every x millis, triggered by a timer.

Is there any memory problem here? Are the unused instances correctly deleted by the garbage collector?

Thanks!

Answer 1

Assuming you have no other references to the instance (or, possibly, its contents), the garbage collector will clean them up. However, the time before cleanup is, as far as I know, indeterminate (there might be some hard timeline in use, but I've never seen it documented). If you're creating a huge number of instances, you might use up a lot of memory before the first ever gets cleaned up.

There is an AS call (the name of which escapes me at the moment) to force a GC run, but it shouldn't normally be necessary. If you find it necessary, you almost certainly need to rethink how your application works.