4.2.2 Impact on the type system

The presence of properties has several consequences on the type system. Most importantly, it is necessary to understand that properties are a compile-time feature and thus require the types to be known. If we were to assign a class with properties to Dynamic, field access would not respect accessor methods. Likewise, access restrictions no longer apply and all access is virtually public.

When using get or set access identifier, the compiler ensures that the getter and setter actually exists. The following code snippet does not compile:

class Main {
  // Method get_x required by property x is missing
  public var x(get, null):Int;

  static public function main() {}
}

The method get_x is missing, but it need not be declared on the class defining the property itself as long as a parent class defines it:

class Base {
  public function get_x() return 1;
}

class Main extends Base {
  // ok, get_x is declared by parent class
  public var x(get, null):Int;

  static public function main() {}
}

The dynamic access modifier works exactly like get or set, but does not check for the existence.

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