return - Is returning early from a function more elegant than an if statement?

Question

Myself and a colleague have a dispute about which of the following is more elegant. I won't say who's who, so it is impartial. Which is more elegant?

public function set hitZone(target:DisplayObject):void
        {
            if(_hitZone != target)
            {
                _hitZone.removeEventListener(MouseEvent.ROLL_OVER, onBtOver);
                _hitZone.removeEventListener(MouseEvent.ROLL_OUT, onBtOut);
                _hitZone.removeEventListener(MouseEvent.MOUSE_DOWN, onBtDown);

                _hitZone = target;

                _hitZone.addEventListener(MouseEvent.ROLL_OVER, onBtOver, false, 0, true);
                _hitZone.addEventListener(MouseEvent.ROLL_OUT, onBtOut, false, 0, true);
                _hitZone.addEventListener(MouseEvent.MOUSE_DOWN, onBtDown, false, 0, true);
            }
        }

...or...

public function set hitZone(target:DisplayObject):void
        {
            if(_hitZone == target)return;

            _hitZone.removeEventListener(MouseEvent.ROLL_OVER, onBtOver);
            _hitZone.removeEventListener(MouseEvent.ROLL_OUT, onBtOut);
            _hitZone.removeEventListener(MouseEvent.MOUSE_DOWN, onBtDown);

            _hitZone = target;

            _hitZone.addEventListener(MouseEvent.ROLL_OVER, onBtOver, false, 0, true);
            _hitZone.addEventListener(MouseEvent.ROLL_OUT, onBtOut, false, 0, true);
            _hitZone.addEventListener(MouseEvent.MOUSE_DOWN, onBtDown, false, 0, true);

        }

Answer 1

In most cases, returning early reduces the complexity and makes the code more readable.

It's also one of the techniques applied in Spartan programming:

Minimal use of Control

1. Minimizing the use of conditionals by using specialized constructs such ternarization, inheritance, and classes such as Class Defaults, Class Once and Class Separator
2. Simplifying conditionals with early return.
3. Minimizing the use of looping constructs, by using action applicator classes such as Class Separate and Class FileSystemVisitor.
4. Simplifying logic of iteration with early exits (via return, continue and break statements).

In your example, I would choose option 2, as it makes the code more readable. I use the same technique when checking function parameters.