JavaScript Spread Operator

Expanding Iterables:

• The spread operator (...) allows expanding iterables like arrays or strings into individual elements.

Array Manipulation:

• Used for combining arrays, creating copies, or passing array elements as function arguments.

String Conversion:

• Converts strings into arrays of characters, facilitating string manipulation.

Example: Array Concatenation

const arr1 = [1, 2, 3];
const arr2 = [4, 5, 6];
const combinedArray = [...arr1, ...arr2];

Example: Creating Array Copies

const originalArray = [1, 2, 3];
const copyArray = [...originalArray];

Example: Passing Array Elements as Function Arguments

const numbers = [1, 2, 3];
const max = Math.max(...numbers);

Example: String Conversion

const str = 'hello';
const chars = [...str];

Object Spread Operator (ES2018):

• Extends object literals by copying own enumerable properties from one or more source objects to a target object.

Example: Object Spread Operator

const obj1 = { a: 1, b: 2 };
const obj2 = { c: 3, ...obj1 };

 

Key Points

• The spread operator simplifies array manipulation and string conversion in JavaScript.
• It offers a concise syntax for combining arrays, creating copies, and passing array elements as function arguments.
• In ES2018, the object spread operator extends object literals, providing a convenient way to merge objects.