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Comment by Tloewald | Hacker News Reader

I'm a bit puzzled what symbols are. If you want a unique thing that !== anything except itself, make an empty object. It seems to me: var foo = Symbol("foo") ought to let you dereference via bar.foo vs. bar[foo] (the latter shouldn't even work!) or it's not what it seems it wants to be.

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Symbol has other traits beyond just not being unique. Properties added via symbols are not iterated over in a for in and do not show up in calls to Object. getOwnPropertyNames()

The point of it is you can implement private properties, as I understand it:

    function MyClass() {
        var mysymbol = new Symbol("foo");
        this[mysymbol] = 3;
    }

    var bar = new MyClass();
    bar.foo // this won't work

What a convoluted mechanism!

What a convoluted mechanism! But where do you keep your reference to the symbol to keep it private? Anywhere you keep it (e.g. in a closure somewhere) that's private doesn't need symbols, so what problem does this solve?

And surely in your private context, bar.foo should still work.

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