Leaking with cycles

One common way to leak objects and their memory is to create strong references between different instances, and cut off any external references.

Let's consider the following code:

class MemoryLeak {
    var ref: MemoryLeak?
    init(ref: MemoryLeak) {
        self.ref = ref
    }

    init() {
        ref = self
    }
}

As you can see, this is some code that you'd be unlikely to write on your own, as it doesn't have a purpose, aside from showcasing a memory leak.

The MemoryLeak class has two initializers, as follows:

• One initializer can take a reference, on to which the instance will hold 
• The other initializer creates a self reference

As you can imagine, this will not bode well if we use that class in code.