Approaching class initializers differently?

I wonder if we could get most of the benefits of class initializers, but approach the issue from the object side. I have no intent of launching a competing proposal (given that I don’t understand all the issues that are involved), but just wanted to put the idea out there.

= Parameterized object literals (POLs) =

Parameterized object literals are a more stylized version of functions that return object literals.
If they assign a prototype, they can be used to implement types.

    function f(a,b) {...} becomes object f(a,b) {...}
    function(a,b) {...} becomes object(a,b) {...}

object Point(x,y) {
    __proto__: {
        dist: function() {
            return Math.sqrt((x*x)+(y*y));
        }
    },
    x: x,
    y: y,
}

object Colored(color) {
    __proto__: {
        describe: function() {
            return "Color: "+this.color;
        }
    },
    color: color
}

// *Not* multiple inheritance (linear chain of types!)
object ColoredPoint(x, y, color)
    extends Point(x,y), Colored(color) {
}

Comments:
- __proto__ is a pseudo-property that can only be set once.
- Getters and setters work like in object literals.
- Still needed: defining property attributes (writable, configurable, enumerable) directly in object literals.
- Possible: init() method that performs additional computations.

Algorithm for type chaining:
- Collect all prototypes (if any) and chain (copies of) them
  - Assign the combined prototype to __proto__ (no prototypes => do nothing)
- Chain the parameterized object literals in a similar manner

Similar to POLs: class initializers [1]:
- Main difference: POLs approach the issue from the object side and increase the declarativeness of what would be the new() method in class initializers.
- Advantage: there is no need to introduce the concept of classes in JavaScript.

[1] http://wiki.ecmascript.org/doku.php?id=strawman:obj_initialiser_class_abstraction

-- 
Dr. Axel Rauschmayer

axel at rauschma.de
twitter.com/rauschma

home: rauschma.de
blog: 2ality.com