The Range attribute

Another thing that we can use to protect our code is the Range attribute. This will allow us to specify a minimum and maximum value for a variable. Since we want the player to always be moving forward, we may want to restrict the player from moving backward. To do that, we can add the following highlighted line of code:

    [Tooltip("How fast the ball moves forwards automatically")] 
    [Range(0, 10)] 
    public float rollSpeed = 5; 

Save your script, and return to the editor:

We have now added a slider beside our value, and we can drag it to adjust between our minimum and maximum values. Not only does this protect our variable, it also makes it so our designers can tweak things easily by just dragging them around.