Truthy & Falsy Javascript

by Mahadevan Sivasubramanian

JavaScript

/************************************* 
 * Truthy and falsy value and equality operator
 */

// falsy value : undefined, null, 0, '', NAN when we evaluate in if else condition
// truthy value : NOT falsy value

var height;

height = 0; // if we just put height = 0 the output will be height is not defined as we already say tht is falsy value but if we want to overcome this we have to put one more condition that is or (||) condition in the if block

if (height || height === 0) {
  console.log('height is defined')
} else {
  console.log('height is not defined')
}