Arrow Functions

Arrow functions function likhne ka ek zyada compact tarika hain — JavaScript mein Python ke lambda ka equivalent, lekin everyday code mein Python ke lambda se kahin zyada commonly use hote hain.

const square = (x) => x * x;
console.log(square(5));

25

(x) => x * x ka matlab hai "ek function jo x leta hai aur x * x return karta hai" — functionally function square(x) { return x * x; } likhne jaisa hi hai, bas ek line mein condense kiya hua. Jab body ek single expression ho, return implicit hota hai — koi return keyword nahi, aur curly braces ki zaroorat nahi.

Arrow functions actually kahan use hote hain

Aap arrow functions ko zyada tar seedhe map() jaise array methods mein pass hote hue dekhoge, jahan ek alag naam wala function define karna itni chhoti cheez ke liye unnecessary ceremony hogi.

const numbers = [1, 2, 3, 4, 5];
const squared = numbers.map((x) => x * x);
console.log(squared);

[ 1, 4, 9, 16, 25 ]

Aage: array methods — map, filter, aur reduce, JavaScript mein collections ko transform karne ka idiomatic tarika.