spread_rest_op.js

// Spread & Rest Operators
/*
Spread: Used to split up arrow elements OR object properties.
const nnewarray = [...oldArray, 1,2]
const newObject = {...oldObject, newProp:5}
Rest: Used to merge a lost of functions argumnets into array.
function sortArray(...arg){
    return args.sort()
}
*/
// Spread Operator.
const numbers = [1, 2, 3 ];
const newNumbers = [...numbers, 4];

console.log(newNumbers);
 /*
 Output: [ 1, 2, 3, 4 ]
 */


 const person = {
     name : "Raza Khan"
 }
 const newPerson = {
     ...person,
     age : 18,
 }
console.log(newPerson.name, newPerson.age);
/*
Output: Raza Khan 18
*/


// Rest Operator
const filter = (...args) => {
    return args.filter(el => el === 1);
}
console.log(filter(1, 2, 3));
/*
Output: [ 1 ]
*/