Question

Is there a way to have a public function from the module-pattern accessing private variables dynamically?
test1 shows what I mean with “access dynamically” but with public variables

var x = (function(){
    var x=0, y=2, z=5;

    return {
        toast: 123,
        test1: function(arg){
            return this[arg];
        },
        test2: function(){
            // ??
        }
    };
}());

console.log(x.test1("toast")); // 123
console.log(x.test2("y")); // should return 2

I ended up with creating a single private variable (an object) storing my private variables so I was able to access them like that

 privateVarStore[privateVarName]

But is there another solution for that?

Answer 1

DEMO

Yes.

Sorry to disappoint Adam Rackis but you can do it with (the evil) eval:

var x = (function(){
    var x=0, y=2, z=5;

    return {
        toast: 123,
        test1: function(arg){
            return this[arg];
        },
        test2: function(a){
            return eval(a)
        }
    };
}());

console.log(x.test1("toast")); // 123
console.log(x.test2("y")); // should return 2  -> does return 2

This is one of those few exceptions where eval should be used.

EDIT, as per Hans B PUFAL suggestion (comment), you can and should validate the parameter in test2 as follows:

test2: function(a){
    return /^[$_a-z][$_a-z0-9]*$/i.test (a) ? eval(a) : undefined;
}