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Comment by thomasfoster96 | Hacker News Reader

It's because the Symbol() function is creating a primitive value, not an object. There is no literal syntax for symbols, as there is for numbers, strings, etc., and so the symbol function is how you make them. Having a symbol constructor would be of little use (it'd be like using new Number()) and so it wasn't included.

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Just to expand on that a bit for anyone who might not know this:

    var s = new String('foo');
    typeof s; // 'object'

That is, when you use the `new` keyword, you get back an object instead of a primitive. Since symbols are always primitives, disallowing the `new` keyword actually prevents inconsistency with the rest of the language in the sense that it doesn't allow you to create non-objects with a constructor.

Strings are always primitives too, but you can call `new String` and receive an object, not an error. This is just straight-up inconsistent, I don't see the point of arguing otherwise.

Take a look at this[0] with regards to strings.

I'm not really sure why you'd use new String anyway - it won't always act as a string primitive. Rather than making Symbol reimplement the same quirks that other built in constructors do, isn't not allowing a Symbol constructor going to avoid a lot of confusion?

For example, if you created an object using a hypothetical symbol constructor, the symbol would be converted to a string if you tried to use it as an object key (internally, JavaScript sees your symbol object as an object, not a symbol), which is simply creating problems for a naive programmer.

[0] https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...

The point under debate is whether it's inconsistent with Number, String, and Boolean, which it is. I agree `new String` is not particularly useful.

Sorry, I think I misunderstood your point. I thought you meant that inconsistency was worse than misusing constructors.

Ok so it's unique in that unlike Number, String, Boolean it has an primitive version but no object version. That could still make it not error when called the same was as other constructors.

> That could still make it not error when called the same was as other constructors.

What do you mean? That new Symbol() should just ignore the 'new'?

'Was' = 'way'. Typo, sorry.

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