Static methods

When a given class calls one of its own static methods (or one from one of its parents), the code should use the self keyword instead of the class name. For more information on when or where static methods are a good idea (or not), see modelling cross cutting concerns.

class MyClass
{
    public static function methodA()
    {
        //...
    }
    public static function methodB()
    {
        // instead of MyClass::methodA():
        self::methodA();
    }
}