ES6 in Depth – Symbols

Re:ES6 in Depth – Symbols by skrebbel on Friday June 12, 2015 @06:09AM (#9704925)

I don't understand why the author compares ES6 symbols to Ruby symbols; they're nothing alike. It's kind of the opposite: Ruby symbols are guaranteed to be the same object if they have the same name, ES6 symbols are guaranteed to be a different object, even if they have the same name (description)

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Re:ES6 in Depth – Symbols by espadrine on Friday June 12, 2015 @06:23AM (#9704977)

  s1 = Symbol.for('cat')
  s2 = Symbol.for('cat')
  s1 === s2  // true

The most common use-case for them is to generate symbols that don't collide, though.

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Re:ES6 in Depth – Symbols by ahoge on Friday June 12, 2015 @08:35AM (#9705433)

`Symbol.for` uses a global registry and the whole thing is "stringly typed".

Looks like an anti-pattern to me.

If you want one particular symbol from some library, you could import it.

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Re:ES6 in Depth – Symbols by artursapek on Friday June 12, 2015 @11:33AM (#9706498)

This was the one thing I didn't understand. Why is using a global Symbol registry any better than just using string properties like usual?

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Re:ES6 in Depth – Symbols by Ded7xSEoPKYNsDd on Friday June 12, 2015 @12:02PM (#9706717)

There won't be a problem if the string happens to be e.g. "toString", I guess. Although they added a 'Map' for that, too.

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Re:ES6 in Depth – Symbols by towelguy on Friday June 12, 2015 @03:25PM (#9708022)

    s1 = Symbol("cat");
    s2 = Symbol.for("cat");
    s3 = Symbol.for("cat");
    s1 == s2; // false
    s2 == s3; // true

You can still have Symbols outside the registry.

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Re:ES6 in Depth – Symbols by artursapek on Saturday June 13, 2015 @09:24PM (#9713460)

That I understand. What I don't understand is why s2 and s3 shouldn't just be vanilla strings.

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