Js The Weird Parts ^new^ -

So next time you see [] + [] returning "" , don’t cry. Laugh. Then fix it. And remember: you’re not alone. What’s the weirdest JavaScript bug you’ve ever encountered? Hit reply or drop a comment—I’d love to compare war stories.

const arr = [1, 2, 3]; arr["foo"] = "bar"; console.log(arr); // [1, 2, 3, foo: "bar"] console.log(arr.length); // 3 (still!) The length property only counts numeric indices. The string key "foo" is there, but the array pretends it isn’t. JavaScript tries to be "helpful" with Automatic Semicolon Insertion (ASI). But sometimes, it helps too much. js the weird parts

And arrow functions? They don’t have their own this at all—they inherit from the surrounding scope. Arrays in JS are just objects with numeric keys and a special length property. That means you can do... questionable things. So next time you see [] + [] returning "" , don’t cry

const bound = showThis.bind("hello"); bound(); // String {"hello"} And remember: you’re not alone

So next time you see [] + [] returning "" , don’t cry. Laugh. Then fix it. And remember: you’re not alone. What’s the weirdest JavaScript bug you’ve ever encountered? Hit reply or drop a comment—I’d love to compare war stories.

const arr = [1, 2, 3]; arr["foo"] = "bar"; console.log(arr); // [1, 2, 3, foo: "bar"] console.log(arr.length); // 3 (still!) The length property only counts numeric indices. The string key "foo" is there, but the array pretends it isn’t. JavaScript tries to be "helpful" with Automatic Semicolon Insertion (ASI). But sometimes, it helps too much.

And arrow functions? They don’t have their own this at all—they inherit from the surrounding scope. Arrays in JS are just objects with numeric keys and a special length property. That means you can do... questionable things.

const bound = showThis.bind("hello"); bound(); // String {"hello"}

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