JavaScript One-Liners to Use in Every Project

Hi, in javascript one-liner refers to concise code snippets that can be written in a single line, the more you get used to it , more easy it becomes

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These one-liners are often used for simplicity, brevity, or to accomplish a specific task quickly. Here are a few examples of common JavaScript one-liners:

//conditional assignment

let value = x || defaultValue;

//ternary operation

let result = condition ? valueIfTrue : valueIfFalse;

//arrow funtion

const double = x => x * 2;

//Array manipulation

const numbers = [1, 2, 3];
const doubledNumbers = numbers.map(x => x * 2);

//object destruction
const { name, age } = person;

//array destruction

const [first, second, third] = array;

//short circuit evaluation

const result = a && b;

//Template literals

const greeting = `Hello, ${name}!`;

//Array filtering

const numbers = [1, 2, 3, 4, 5];
const evenNumbers = numbers.filter(x => x % 2 === 0);

//object shorthand

const name = "John";
const age = 30;
const person = { name, age };

//Array sum
const numbers = [1, 2, 3, 4, 5];
const sum = numbers.reduce((total, num) => total + num, 0);

//object mapping

const users = [
  { id: 1, name: "John" },
  { id: 2, name: "Jane" },
  { id: 3, name: "Bob" }
];
const userIdMap = users.reduce((map, user) => ({ ...map, [user.id]: user }), {});

//Flatten an array
const nestedArray = [[1, 2], [3, 4], [5, 6]];
const flattenedArray = nestedArray.reduce((flat, arr) => [...flat, ...arr], []);

//find maximum value
const numbers = [10, 5, 8, 2, 7];
const maxNumber = Math.max(...numbers);

//Remove duplicates from an array
const numbers = [1, 2, 3, 4, 4, 5, 5];
const uniqueNumbers = [...new Set(numbers)];

//group object by property

const users = [
  { id: 1, name: "John", group: "A" },
  { id: 2, name: "Jane", group: "B" },
  { id: 3, name: "Bob", group: "A" }
];
const groupedUsers = users.reduce((groups, user) => ({ ...groups, [user.group]: [...(groups[user.group] || []), user] }), {});

//Genarate an array range
const start = 1;
const end = 5;
const range = Array.from({ length: end - start + 1 }, (_, index) => start + index);

//swap variables
let a = 5;
let b = 10;
[a, b] = [b, a];

//Capitalize first letter of each word in a sentence
const sentence = "hello world";
const capitalized = sentence.replace(/\b\w/g, match => match.toUpperCase());

// just for fun , doing fabonacci sequence in one-line
const fibonacci = n => Array.from({ length: n }, (_, i) => i > 1 ? fibonacci[i - 1] + fibonacci[i - 2] : i);

Remember, while one-liners can be powerful, readability and maintainability should always be prioritised when writing code.

Thank you… 😉