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ES6 Tutorials : SPREAD Operator with Fun
JavaScript ES6 (ECMAScript 6) introduced the spread operator. The syntax is three dots(...) followed by the array (or iterable*). It expands the array into individual elements. So, it can be used to expand the array in a places where zero or more elements are expected.
1. Copying an array
let fruits = ['Apple','Orange','Banana'];
let newFruitArray = [...fruits];
console.log(copiedList); // ['Apple','Orange','Banana']
2. Concatenating arrays
let arr1 = ['A', 'B', 'C'];
let arr2 = ['X', 'Y', 'Z'];
let result = [...arr1, ...arr2];
console.log(result); // ['A', 'B', 'C', 'X', 'Y', 'Z']
3. Spreading elements together with an individual element
let fruits = ['Apple','Orange','Banana'];
let newFruits = ['Cherry', ...names];
console.log(newFruits); // ['Cherry', 'Apple','Orange','Banana']
4. Spreading elements on function calls
let fruits = ['Apple','Orange','Banana'];
var getFruits = (f1, f2, f3) => {
console.log(Fruits: ${f1}, ${f2} and ${f3}
);
};
getFruits(...fruits); // Fruits: Apple, Orange and Banana
5. Spread syntax for object literals
var obj1 = { id: 101, name: 'Jhon Doe' }
var obj2 = { age: 25, country: 'USA'}
const employee = { ...obj1, ...obj2 }
console.log(employee); //{ "id": 101, "name": "Jhon Doe", "age": 25, "country": "USA" }
For more questions on ES6 please visit - https://rapides6.herokuapp.com
Solve, Learn and have Fun :)
####Learn about ES6 - Default Parameters here - https://tech.io/playgrounds/7337/es6-tutorials---your-guide-for-quick-checks