86 lines
2.5 KiB
Plaintext
86 lines
2.5 KiB
Plaintext
|
/**
|
||
|
|
* Proof of concept for Object-Oriented Programming in Boppi.
|
||
|
|
* Note that this is a very basic notion of OO that only includes private
|
||
|
|
* members. It does not support type checking, inheritance or public members.
|
||
|
|
* It requires a tremendous amount of boilerplate to work without proper
|
||
|
|
* tuples, parametrization or OO class syntax.
|
||
|
|
*/
|
||
|
|
|
||
|
|
//Declaring dummy functions for type aliases because Boppi disallows
|
||
|
|
//the use of Void directly in a type.
|
||
|
|
function intToVoid(int a) 0;
|
||
|
|
function int voidToInt() 0;
|
||
|
|
function class() 0;
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
//Class declaration whose sole purpose is to make the code look better.
|
||
|
|
//`Rectangle` type checks with every other `()->Void` type.
|
||
|
|
var class Rectangle;
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
//Helpers for making methods available outside their closure (the function
|
||
|
|
//references should be passed via a return value if tuples were supported)
|
||
|
|
//Assigning them immediately to suppress warnings.
|
||
|
|
var voidToInt _getWidth; _getWidth := voidToInt;
|
||
|
|
var intToVoid _setWidth; _setWidth := intToVoid;
|
||
|
|
var voidToInt _getHeight; _getHeight := voidToInt;
|
||
|
|
var intToVoid _setHeight; _setHeight := intToVoid;
|
||
|
|
var voidToInt _getArea; _getArea := voidToInt;
|
||
|
|
|
||
|
|
//Wrappers to make a `getWidth()` call less of an eyesore and allow you
|
||
|
|
//to nest these calls without overriding the target closure in between
|
||
|
|
function int getWidth (Rectangle rect) { rect();_getWidth() };
|
||
|
|
function setWidth (Rectangle rect, int width) { rect();_setWidth(width) };
|
||
|
|
function int getHeight(Rectangle rect) { rect();_getHeight() };
|
||
|
|
function setHeight(Rectangle rect, int height) { rect();_setHeight(height) };
|
||
|
|
function int getArea (Rectangle rect) { rect();_getArea() };
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
//A class definition looks decent apart from the bind function to expose
|
||
|
|
//the class methods. You can even add constructor arguments to your liking.
|
||
|
|
function Rectangle newRectangle() {
|
||
|
|
var int width;
|
||
|
|
var int height;
|
||
|
|
|
||
|
|
function int getWidth()
|
||
|
|
width;
|
||
|
|
|
||
|
|
function setWidth(int newWidth) {
|
||
|
|
width := newWidth;
|
||
|
|
};
|
||
|
|
|
||
|
|
function int getHeight()
|
||
|
|
height;
|
||
|
|
|
||
|
|
function setHeight(int newHeight) {
|
||
|
|
height := newHeight;
|
||
|
|
};
|
||
|
|
|
||
|
|
function int getArea()
|
||
|
|
width*height;
|
||
|
|
|
||
|
|
|
||
|
|
function bind() {
|
||
|
|
_getWidth := getWidth;
|
||
|
|
_setWidth := setWidth;
|
||
|
|
_getHeight := getHeight;
|
||
|
|
_setHeight := setHeight;
|
||
|
|
_getArea := getArea;
|
||
|
|
};
|
||
|
|
bind
|
||
|
|
};
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
//Time to use the class
|
||
|
|
var Rectangle a; a := newRectangle();
|
||
|
|
var Rectangle b; b := newRectangle();
|
||
|
|
|
||
|
|
setWidth(a, 4);
|
||
|
|
setWidth(b, getWidth(a)+2);
|
||
|
|
setHeight(b, 3);
|
||
|
|
print(getArea(b));
|