PHP

OO

• namespace?
• interface?
• self?
• $this?
• use?
• annotations?
• visibility:
  • private: only in this class
  • protected: only in derived classes
  • public: everywhere
• ctor

function __construct() {
  parent::__construct(); // has to be called explicitly
  ...
}

• dtor

function __destruct() {
  parent::__destruct(); // has to be called explicitly
}

• trait: a trait is similar to a class, but only intended to group functionality in a fine-grained and consistent way. It is not possible to instantiate a Trait on its own. It is an addition to traditional inheritance and enables horizontal composition of behavior; that is, the application of class members without requiring inheritance.