closes #2600
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@ -38,7 +38,12 @@ Why `user2.name` is `undefined`?
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Here's how `new user.constructor('Pete')` works:
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1. First, it looks for `constructor` in `user`. Nothing.
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2. Then it follows the prototype chain. The prototype of `user` is `User.prototype`, and it also has nothing.
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3. The value of `User.prototype` is a plain object `{}`, its prototype is `Object.prototype`. And there is `Object.prototype.constructor == Object`. So it is used.
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2. Then it follows the prototype chain. The prototype of `user` is `User.prototype`, and it also has no `constructor` (because we "forgot" to set it right!).
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3. Going further up the chain, `User.prototype` is a plain object, its prototype is the built-in `Object.prototype`.
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4. Finally, for the built-in `Object.prototype`, there's a built-in `Object.prototype.constructor == Object`. So it is used.
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At the end, we have `let user2 = new Object('Pete')`. The built-in `Object` constructor ignores arguments, it always creates an empty object, similar to `let user2 = {}`, that's what we have in `user2` after all.
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Finally, at the end, we have `let user2 = new Object('Pete')`.
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Probably, that's not what we want. We'd like to create `new User`, not `new Object`. That's the outcome of the missing `constructor`.
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(Just in case you're curious, the `new Object(...)` call converts its argument to an object. That's a theoretical thing, in practice no one calls `new Object` with a value, and generally we don't use `new Object` to make objects at all).
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