JAVASCRIPT

javascript default parameters

function multiply(a, b = 1) {
  return a * b;
}

how to set default value to variable in javascript

 name = name || 'no name';

js default parameter

function read_file(file, default_param = false) {
  // Code
}

javascript ES6 Default Parameter Values

function sum(x, y = 5) {

    // take sum
    // the value of y is 5 if not passed
    console.log(x + y);
}

sum(5); // 10
sum(5, 15); // 20

js default parameter

function greeting (name = 'stranger') {
  console.log(`Hello, ${name}!`)
}

greeting('Nick') // Output: Hello, Nick!
greeting() // Output: Hello, stranger!

javascript default function parameter value

function multiply(a, b) {
  b = (typeof b !== 'undefined') ?  b : 1
  return a * b
} 

How Do Default Parameters Work in JavaScript?

// Default parameters let you assign a default value to a parameter when you define a function. For example:

function greeting(name, message = ”Hello”){
	console. log(`${messgae}  ${name}`)
}

greeting(‘John’); //output: Hello John

//you can also assign a new value to the default parameter 
//when you call the function

greeting(‘Doe’, ‘Hi’); //output: Hi Doe

JavaScript Default Parameters

function sum(x = 3, y = 5) {

    // return sum
    return x + y;
}

console.log(sum(5, 15));  // 20 
console.log(sum(7));        // 12
console.log(sum());          // 8

javascript Passing Parameter as Default Values

function sum(x = 1, y = x,  z = x + y) {
    console.log( x + y + z );
}

sum(); // 4

Default Parameter Values in javascript

// Default Parameter Values in javascript
// Longhand:
function volume(l, w, h) {
    if (w === undefined)
      w = 3;
    if (h === undefined)
      h = 4;
    return l * w * h;
  }
console.log(volume(2)); //output: 24
  
// Shorthand:
volume_ = (l, w = 3, h = 4 ) => (l * w * h);
console.log(volume_(2)) //output: 24