1/10/2018 - 1:53 PM


Examples Examples of falsy values in JavaScript (which translate to false and thus bypass the if block):

if (false) if (null) if (undefined) if (0) if (NaN) if ('') if ("") if (document.all) [1] [1] document.all has been used for browser detection in the past and the HTML specification defines a willful violation of the ECMAScript standard here to keep compatibility with legacy code (if (document.all) { // Internet Explorer code here } or using document.all without checking its presence first: document.all.foo).

Sometimes written falsey, although in English usually turning a word into an adjective with a -y, any final e is dropped (noise => noisy, ice => icy, shine => shiny)