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Using JavaScript classes without the `class` keyword

Corbin Crutchley on June 29, 2023

Classes in JavaScript are both powerful and weird. While they allow us to create named objects with similarly purposed methods and properties, they...

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Eckehard • Jul 1 '23

People are used to use all kind of "tricks" in Javascript.

    const sqr = (x) => x*x
    console.log(sqr(3))

Everybody knows, this defines a function, but WHY do we use a language, that states to define a constant, but creates a function instead? Why does a language allow to use this kind of ambiguity?

There are a lot of good reasons, why things are a bit wiered in JS, but not everybody is happy to use a language like a shell game. Classes make Javascript more explicit. If you define a class using the CLASS-keyword, everybody will know your intention. This is often not the case with common Javascript code...

Corbin Crutchley Playful Programming • Jul 2 '23

I mean, I'm on board with the class keyword. This wasn't a slam piece, it was to help folks understand historical context of the language and maybe even understand the prototype system better

Eckehard • Jul 2 '23

Of course, thank you very much for your effort. I just wanted to note, that it is not a advantage to define a class without using the keyword. Even if it was only "syntactical shugar" (which i think it is not), it is better to use a clear naming for things you do.

We should always be clear that a programming language is made for programmers, not for computers. A computer uses opcodes, so in that case we should use assembler.

Vladas Saulis • Jul 3 '23

IMO computer languages are made for computers, - not for programmers. When you start realize it, programming will make easier.

Eckehard • Jul 3 '23

Sy, why do we not use assembler? It is much easier to understand for a computer...

Vladas Saulis • Jul 3 '23

Mostly we use heavy-weight frameworks which finally generate assembler/machine code for computers, not for you.

Vladas Saulis • Jun 29 '23 • Edited

I always knew that classes in JS are just syntactic sugar.

Uriel dos Santos Souza • Jun 30 '23

No!

JS classes are not “just syntactic sugar” | by Andrea Giammarchi | Medium

Andrea Giammarchi ・ Jun 30, 2021 ・
webreflection.Medium

Classes, Not Just Syntactic Sugar

Parwinder 👨🏻‍💻 ・ Sep 4 '20 ・ 3 min read

#javascript #beginners #codenewbie #webdev

Class is not just a Syntactic sugar in Javascript | by Arun Rajeevan | Medium

Arun Rajeevan ・ Jul 12, 2019 ・
arunrajeevan.Medium

Vladas Saulis • Jun 30 '23

I always convert JS classes into prototype chains without any consequences.

went • Jul 3 '23 • Edited

Please fix the error of re-assigning Corbin.prototype, instead of :

Corbin.prototype = Object.create(Person.prototype);

much better do the following:

Object.setPrototypeOf(Corbin.prototype, Object.create(Person.prototype))

Because otherwise Corbin instance is not a member of Corbin constructor if you will use instanceof for check...

Seems there is a non-enumerable .constructor property in Corbin.prototype, accordingly with the specification, which is then used for matching instanceof. And when you just re-assign ... you deleting it.

And for sure instead of code above you may also go like this:


function Person() {
}
Person.prototype.personality = "quirky";

function Corbin() {
}
Corbin.prototype = Object.create(Person.prototype, {
    constructor: { value: Corbin },
    name: { value: "Corbin" }
});

const corbin = new Corbin;
console.log(corbin instanceof Person); // true
console.log(corbin instanceof Corbin); // true