Grok all the things

grok (v): to understand (something) intuitively.

JavaScript

🙄  Cynics & grumps

Ah, JavaScript. The language that, despite its many quirks and flaws, somehow managed to become the backbone of modern web development. Love it or hate it, you simply can't avoid it. So let's dive into the beautiful mess that is JavaScript and see if we can find some twisted sense of enjoyment in its peculiarities.

JavaScript was created in 1995 by Brendan Eich in just 10 days, and it shows. Originally named Mocha, then LiveScript, and finally JavaScript, it was designed to be a lightweight scripting language for the web. As the saying goes, "Java is to JavaScript as ham is to hamster" - a fact that doesn't stop people from confusing them constantly.

Initially intended to make web pages more interactive, JavaScript has now infiltrated every layer of development, from front-end to back-end, and even into mobile app development with technologies like React Native. No one saw that coming.

The language is full of oddities, like its type coercion system. Let's take a look at this gem:

"5" + 3 // "53"
"5" - 3 // 2

Why? Because JavaScript is just so helpful in trying to figure out what you meant. Adding a string and a number? No problem, it'll just convert the number to a string and concatenate them for you. Subtracting a string and a number? It'll assume you meant to perform mathematical subtraction and convert the string to a number. Confusing? You bet.

And let's not forget about the infamous == vs ===. JavaScript thought it was a good idea to have two equality operators, one of which (==) performs type coercion, while the other (===) does not. This leads to some truly baffling results:

null == undefined // true
null === undefined // false
"5" == 5 // true
"5" === 5 // false

As a result, developers are often advised to use === and !== to avoid unexpected surprises. Because who needs simplicity when you can have twice the fun?

JavaScript's scoping rules are another source of confusion. The language originally had only function-level scoping, so variables declared with var were accessible outside of the block they were defined in:

for (var i = 0; i < 5; i++) {
  // ...
}
console.log(i); // 5

But fear not, for JavaScript has given us let and const to declare block-scoped variables. This means you now have three different ways to declare variables, each with their own quirks. Progress!

One of JavaScript's most polarizing features is its prototype-based inheritance model. Instead of traditional class-based inheritance, JavaScript uses prototypes to share properties and methods between objects:

function Person(name) {
  this.name = name;
}

Person.prototype.sayHello = function() {
  console.log("Hello, my name is " + this.name);
};

const alice = new Person("Alice");
alice.sayHello(); // "Hello, my name is Alice"

This unconventional approach to inheritance is often criticized for being unintuitive and verbose. And yet, JavaScript doubled down on the confusion by introducing ES6 classes, which are just syntactic sugar over the prototype-based system:

class Person {
  constructor(name) {
    this.name = name;
  }

  sayHello() {
    console.log("Hello, my name is " + this.name);
  }
}

const alice = new Person("Alice");
alice.sayHello(); // "Hello, my name is Alice"

Sure, it looks like a class, but don't be fooled - it's still just prototypes in disguise.

And finally, there's the callback hell. JavaScript's asynchronous nature, while powerful, often leads to deeply nested callbacks that make code difficult to read and maintain. But hey, at least we've got Promises and async/await now to alleviate some of that pain, right?

In conclusion, JavaScript is a flawed, quirky, and oftentimes bewildering language. But it's also incredibly versatile and ubiquitous. So whether we like it or not, we're stuck with it. Might as well embrace the chaos and find some twisted pleasure in mastering its eccentricities. Happy coding!

Grok.foo is a collection of articles on a variety of technology and programming articles assembled by James Padolsey. Enjoy! And please share! And if you feel like you can donate here so I can create more free content for you.