Question

Which is the best way to reference a private method from returned object in javascript? I leave you some sample code:

var HelloWorld = (function(){
    var hello = function(){
        console.log("hello")
    },
    return{
        addToList: function(){
            //how can i reference hello from here dynamically like:
                            //this["hello"] or this["hell" + "o"]
        }       
    }
})()

Answer 1

hello() is not a method. It’s just a function in a closure. So, you can just call it from within your addToList() method.

If you want the hello function to behave like a method with this set to the object instance, you’d have to pass the instance to it as in this example.

var HelloWorld = (function(){
    var hello = function(){
        console.log("hello")
    },
    return{
        addToList: function(){
            //how can i reference hello from here dynamically like:
            hello.call(this);
        }       
    }
})()

---

If what you’re really trying to do is to access the hello function by a string reference, you cannot easily access local variables by string name. If you wanted to do that, you could have to put the hello function into a local object like this:

var HelloWorld = (function(){
    var locals = {
        hello: function(){
            console.log("hello")
        }
    };
    return{
        addToList: function(){
            //how can i reference hello from here dynamically like:
            locals["hello"].call(this);
        }       
    }
})()