Unreal Development Kit Game Programming with UnrealScript：Beginner's Guide

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Time for action – Experiments with inheritance

Let's add a variable to our AwesomeGun class and see how it works with another class we'll create.

Add an int to our AwesomeGun class called MyInt. Our code should now look like this:

class AwesomeGun extends UTWeap_RocketLauncher_Content;

var int MyInt;
defaultproperties
{
    FireInterval(0)=0.1
    ShotCost(0)=0
}

Now create another class in our AwesomeGame/Classes folder called AnotherGun.uc. Type the following code into it:
```
class AnotherGun extends AwesomeGun;

defaultproperties
{
    MyInt=4
}
```
Compile the code. We'll see that it compiles fine as our AnotherGun is inheriting MyInt from AwesomeGun.
Now let's change the class we're extending from to be the same as AwesomeGun's parent class:
```
class AnotherGun extends UTWeap_RocketLauncher_Content;

defaultproperties
{
    MyInt=4
}
```

Now when we compile, we'll get a warning:

Warning, Unknown property in defaults: MyInt=4

What just happened?

Even though the classes extend off of the same class, inheritance only happens when the class we want to use the variable in is inside the one that declares the variable in the class tree. We can change the default property of the variable for our class, and this is how we get different functionality out of them such as our example with the firing rate.