JAVASCRIPT

How Do Rest Parameters Work in JavaScript?

// With rest parameters, you can define a function to store multiple arguments in a single array

function sayHello(message, ...names){
  names.forEach(name => console.log(`${message} ${name}`));
}

sayHello('Hello', "John", "Smith", "Doe");

/*
output:

Hello John

Hello Smith

Hello Doe 

*/

// The ... is what makes names a rest parameter.

rest parameters javascript

/*
That allows a function to accept an indefinite number of arguments as an array
*/
function fun(...input){
    let sum = 0;
    for(let i of input){
        sum+=i;
    }
    return sum;
}
console.log(fun(1,2)); //3
console.log(fun(1,2,3)); //6
console.log(fun(1,2,3,4,5)); //15 

javascript rest parameter

function show(a, b, ...args) {
  console.log(a); // one
  console.log(b); // two
  console.log(args); // ["three", "four", "five", "six"]
}

show('one', 'two', 'three', 'four', 'five', 'six')

javascript Rest Parameter

let func = function(...args) {
    console.log(args);
}

func(3); // [3]
func(4, 5, 6); // [4, 5, 6]

rest parameters javascript

/*The rest parameter syntax allows a function to accept an indefinite
number of arguments as an array, */

function getFirstElementOfArray(...args){
  return args[1]
}

getFirstElementOfArray("shirshak","Sabtech","Javascript")// return shirshak