Haxe has a unique way of using getter/setter functions and it can be sometimes confusing for developers coming from other languages.
I recommend to read the official documentation as well.
Getter and Setter
You can define a variable to have getter and setter functions using get and set keywords as shown below.
The functions names should be prefixed with get_ variable name and set_ variable name.
public var amount(get, set):Float;
var _amount:Float = 100;
function get_amount():Float {
return _amount * 10;
}
function set_amount(value:Float) {
return _amount = value;
}The most important thing to note here is you cannot access the physical variable inside your getter and setter functions. You get the error This field cannot be accessed because it is not a real variable if you try to access amount inside get_amount and set_amount functions.
To access physical variable you need to add metadata @:isVar in front of the variable amount.
@:isVar public var amount(get, set):Float;
function get_amount():Float {
return amount;
}
function set_amount(value:Float) {
return amount = value;
}Getter (read-only) or Setter (write-only)
By using null in place of set you can mark the variable read-only with getter function as shown below.
public var language(get, null):String;
function get_language():String {
return language;
}Similarly by using null in place of get you can mark the variable write-only with setter function as shown below.
public var language(null, set):String;
function set_language(value:String):String {
return language = value;
}The variable can still be accessed for reading and writing within the class but not from outside.
Setter with default Getter
By using default in place of get you can mark the variable to return it’s value when accessed and still have a setter function.
public var language(default, set):String;
function set_language(value):String {
return language = value;
}Quick Reference
//Read and write access from anywhere but only exception is the physical variable cannot be accessed within getter and setter functions without metadata @:isVar
public var x(get, set):Float;
//Can be read from anywhere, modified only within the class
public var x(default, null):Float;
//Can be set from anywhere, modified only within the class
public var x(null, default):Float;
//Read-only from anywhere even within the same class
public var x(get, never):Float;
//Read and write access from anywhere, but the setter needs a method
public var x(default, set):Float;
//not allowed - unsupported property combination
public var x(get, default):Float;