向对象常量中定义的对象构造函数添加原型

Question

Hey so I have an object constructor method inside and object literal, and I defined a prototype for the constructor like this

objectLiteralKey:(function()
{
    var f=function()
    {
        ...
    };

    f.prototype=ObjectInstance;

    return f;
}()),
//inside an object literal

is there any reason this pattern of defining the prototype should be avoided? or perhaps another way thats better somehow?

EDIT: by the way the object literal is within a self invoking function which holds the laserPrototype, I put it there because there is another "enemy" that requires the same prototype

full code http://jsfiddle.net/m2DwT/

Answer 1

is there any reason this pattern of defining the prototype should be avoided?

No. Apart from readability, maybe.

or perhaps another way thats better somehow?

I think there are too many unecessary immedieately invoked function expressions in your code, which you could omit. It might be better to put the constructors right before their prototype:

var laser = (function () {
    var eLasers = []; // local variable declarations
    var pLasers = []; // for encapsulation

    function Player() {
        this.x = window.player.x; // wait, what? Maybe parameters
        this.y = window.player.y; // would fit better.
        pLasers.push(this);
        this.destroy = function () {
            pLasers.splice(pLasers.indexOf(this), 1);
        }
    }
    function Enemy() {
        …
    }
    // here, Player.prototyp !== Enemy.prototype
    // but I don't think that is really necessary
    Player.prototype.draw = Enemy.prototype.draw = function() {
        ctx.beginPath();
        ctx.arc(this.x, this.y, 5, 0, 2 * Math.PI);
        ctx.stroke();
    };

    return {
        enemy: Enemy,
        player: Player,
        step: …
    }
}())