Creating a new object within namespace javascript

Question

I'm trying to create a function within a namespace that will get me a new object instance.

I get syntax error trying to do the following:

var namespace = {
    a : function(param){
        this.something = param;
    },
    a.prototype.hi = function(){
        alert('hi');
    },

    b : function(){
        var t = new a('something');
    }
};

What is the correct syntax for doing this? Is it not possible to do within the namespace object? I don't want to declare the namespace first. Thanks

Duplicate. See this SO answer for a way of doing it: http://stackoverflow.com/questions/7137860/javascript-namespace-declaration-with-function-prototype — Eli Gassert, Dec 03 '12 at 16:15
Thanks Eli - I knew there had to be a simple way to do this, seems very common to me. Unfortunately I have to do some code refactoring now but I don't think it will be too bad. — JavaKungFu, Dec 03 '12 at 16:18

score 7 · Accepted Answer · edited Jul 16 '14 at 16:40

I don't want to declare the namespace first.

You can do weird things like this:

var namespace = {
    init: function() { 
        a.prototype.whatever = function(){};
    },
    a: function(x) {
        this.x = x;
    }  
}
namespace.init();
var myA = new namespace.a("x");

But why not try the module pattern if you want to encapsulate everything? It's way cleaner:

var namespace = (function() {
     function a() {};
     function b(name) {
          this.name = name;
     };
     b.prototype.hi = function() {
          console.log("my name is " + this.name);
     }
     return {
          a: a,
          b: b
     }
})();

Thanks I think I will refactor to use the module pattern. – JavaKungFu Dec 03 '12 at 16:20 — JavaKungFu, Dec 03 '12 at 16:20

score 0 · Answer 2 · answered Dec 03 '12 at 16:13

0

A javascript namespace is an object so you can only use key: value couples but no code (as you do with : a.prototype.hi = function() {...}).

You should thus separate that in two : declaration and then code :

var namespace = {
    a : function(param){
        this.something = param;
    },
    b : function(){
        var t = new a('something');
    }
};

namespace.a.prototype.hi : function() { ... }

answered Dec 03 '12 at 16:13

Samuel Caillerie

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I'm not sure what your comment means "no code" - that's clearly not true. – JavaKungFu Dec 03 '12 at 16:19
Yes, probably is it badly formulated, here it is the "key" `a.prototype.hi` which is impossible in a javascript object, but in the value you can add whatever code you want! – Samuel Caillerie Dec 03 '12 at 16:20

score 0 · Answer 3 · answered Dec 03 '12 at 16:19

I do not exactly know what you want, but this works:

var namespace = {

    a: function() {

        function a() {

        }

        a.prototype.hi = function() {
            console.log("hi");
        }

        return new a;

    }

}

var obj = new namespace.a();
obj.hi()

// -> 'hi'

Creating a new object within namespace javascript

3 Answers3