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Comment by lobstrosity420 | Hacker News Reader

They weren’t criticizing OOP per se. Before the class keyword, JavaScript had much more powerful OOP semantics using metaobjects.

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The class keyword is just syntactic sugar. JS still uses prototypal inheritance. Nothing has changed. Check out objectplayground.com for details.

Not ‘nothing’ has changed. Classes are supposed to be syntactic sugar over constructor functions, but the later could be invoked as well as instantiated with the ‘new’ keyword, whereas the interpreter will error out on you if you attempt to invoke a class. That is fine though, I don’t care for constructor functions. I was talking about using metaobjects, a different concept altogether.

Okay, I think I get your complaint. JavaScript doesn’t have a metaobject protocol, but there were a variety of user-land approaches to OOP that added one. Although they’re still technically possible, the class syntax formalized a non-MOP approach to OOP, and those third-party tools have all fallen by the wayside.

It’s not so much that you can’t use a MOP in JS, so much that people don’t, and will look at you funny if you do.

As a lover of simple and straightforward code, I never used the MOPs—I hand-coded “class.prototype.method = function()” like God intended*—and I’m happy the standard uses that more traditional approach. But I can see how someone who did use a MOP would feel that the class syntax is a step backwards.

*that’s a joke.

Yes, this is it. The MOP approach basically involves using ‘Object.assign’ to instantiate new objects from the metaobject. It is quite straightforward in my opinion, but that is relative I suppose. I don’t know if this is true but I’ve been told that Brendan Eich intended for this exact approach to be the one and true OOP in JS, but was persuaded by his boss to implement constructor functions to make it more like Java.

That'd be a little weird if that was Eich's "original vision" considering `Object.assign` didn't come out until ES6. Which was also when the `class` keyword was introduced.

Good catch. It’s been a while since I’ve been thought the ways of old JS so I’m misremembering. It’s all apocryphal anyhow.

It's not apocryphal if I'm the source. I wanted Self-ish prototypes and cloning but "Make It Look Like Java" orders trumped my wishes.

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