28 JavaScript One-Liners every Senior Developer Needs to Know

1. Swapping Values Without a Temporary Variable

let a = 1, b = 2;

[a, b] = [b, a];

// Output: a = 2, b = 1

This one-liner uses array destructuring to swap the values of a and b without needing a temporary variable. It's a neat trick that makes your code cleaner and more concise. The [a, b] = [b, a] syntax swaps their values by destructuring the array on the right-hand side and assigning it to the left-hand side.

2. Object Destructuring for Easier Data Access

const {name, age} = {name: 'John', age: 30};

// Output: name = 'John', age = 30

Here, object destructuring is used to extract name and age properties from an object directly into variables. This approach simplifies accessing object properties and enhances code readability.

3. Cloning Objects in a Snap

const originalObj = {name: 'Jane', age: 22};

const clonedObj = {...originalObj};

// Output: clonedObj = {name: 'Jane', age: 22}

The spread operator (...) is utilized to create a shallow clone of originalObj. This technique copies all enumerable own properties from the original object to a new object.